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Fridge Brilliance
Venom is completely right at being mad when called a "parasite". In biology there are two types of symbiosis: mutualism, where both species are benefited by the bond, and parasitism, where one species is benefited by the other, that is impaired or even killed by the relation. Riot is clearly a parasite, using and disposing of hosts at will (and yes, "host" is the correct term). And the Brock-symbiote relation is a case of mutualism, as long as the symbiote stays true to its word of not eating Brock's body organs. The symbiote can survive in earth's environment and Brock's body has increased powers, so the benefit is mutual.
Also serves as a My Species Doth Protest Too Much. The symbiote's mutualism is undercut by it feeding on the host's organs if it doesn't gain enough of its own nutrition. When Venom is called out on this, it calls out "I can fix it" in a very defensive manner. It's ashamed that it is in fact acting like a parasite.
Actually, there's a third type of symbiosis: commensalism. This is where the host organism isn't much affected one way of the other by the symbiote's presence, such as the remora, a fish that suctions itself onto a larger fish and eats their table scraps. It's also worth noting that which category a symbiote falls into isn't always clear-cut. Mycorrhiza fungi, for example, engage in symbiosis with plants. And the relationship has benefits and tradeoffs on the plant's part. The pros only outweigh the cons if nutrient availability is somewhat low. Venom would seem to be the inverse of this.
There's a practical reason why the Venom symbiote would want Eddie and Anne to reconcile and hook up again. Venom bonded with Anne so that they could save Eddie from the Life Foundation. They must have been bonded for some time to get from the hospital to Eddie in time. When Venom returns to Eddie, Anne shows zero negative effects, meaning she, like Eddie, is a perfect match for Venom. The symbiote would want two perfect hosts nearby should the need arise.
Also, we haven't got a concrete answer as to whether or not Venom can extend Eddie's lifespan. Venom may be trying to breed a steady supply of suitable hosts.
Venom's species also feeds on phenylethylamine, which it normally gets by eating brains (and later chocolate). One of its key roles is in producing hormones related to euphoria, sex and romance included. It's probably getting a boost out of the relationship.
There is also the thought that Venom is very selfish with 'his' toys. Since Anne 'belonged' to Eddie at one time, what was Eddie's is now Venom's. Venom just wants his toys where they belong.
Venom was also in both of their heads and saw their memories. It also knows that they still care for each other, so it probably believes they should be together. Since it was in both of their heads, it had access to all of the happy memories they shared and experienced the love they had and still have. It most likely took on bits of that attraction and warmth from sharing both of their perspectives and feels that it is right that they be together.
Venom does not recognize Stan Lee. And why should it? Venom was created in 1988 by David Michelinie and Todd McFarlane, long after Stan Lee ceased writing comics.
It also served as a joke though, since most people know who Lee is.
Drake apologizes to Riot for getting its fellow symbiotes killed. However, he's apologizing to a creature inhabiting his body, so it's less heartwarming and more sucking-up to a creature who can enable his survival.
Riot probably knows Drake is full of it and was only experimenting on its species, since when symbiotes bond they know all their host knows. But it doesn't care, since there are others.
On the other hand, Drake is pretty angry whenever a symbiote dies. He has decided that humans are too flawed, while symbiotes are capable of surviving in space and can adapt pretty well, making them "better" in his mind. He's not apologizing for the loss of lives (we see that he has no issue with killing off people), but for the loss of resources, a view that Riot shares (considering how it brushes the deaths off and deals with Venom), and that's why they bond pretty well (despite leaving no autonomy to other hosts and not needing to for Drake to have the rocket ready, Riot seems to only take direct control while fighting).
It's shown at one point that Venom was damaging Eddie's internal organs, but it said it could 'fix that'. If what was shown on screen was all they did with it, then it likely only had two or three prior human hosts, and maybe a couple of animal hosts. In short, it's not used to human anatomy, so it didn't realize the damage it was causing. And seeing how Anne didn't have any negative effects from bonding, then Venom clearly learned, and it learned fast.
Alternatively, it was consuming those organs because it was starving. Once it had enough food, that wasn't necessary anymore.
Which leads to Fridge Horror; how did Kasady cut himself?
The human body does have some parts that can cut built in, nails and teeth. Alternatively, there could be a sharp point somewhere in his cell.
Notice there is no spider insignia on Venom, or web shooting in this film. That's because this version hasn't met Spider-Man/Peter Parker (If he even exists in this world).
Although it did replace web with goo slinging in a short scene.
Venom being less evil in the film actually makes sense. There is no Peter Parker around to "torment" Eddie. In the comics, he blamed Spider-Man for all of his problems. His hatred for Peter drove him insane. And the symbiote hated Spider-Man just as much for rejecting it (the relationship is often, subtly or not, played as the symbiote essentially being an overpossessive psycho ex). Eddie and Venom initially bonded over that shared hate, which made for an Ax-Crazy villain obsessed with Spider-Man. Without that, Eddie and Venom are free to skip to all the Character Development they got as they learned to let go of that hate and focus on other things.
A plot point is made of how the symbiote needs a compatible host and how quickly it destroys the others, yet Riot immediately finds a host capable of hosting it for months. However, as Venom states, it has superior abilities compared to regular symbiotes, and we see an example by it being able to create blades or even solidify parts of its body and use them as projectiles. It's possible that either making more lasting hosts out of worse matches or identifying how compatible a host is on sight is another of those abilities, if not both of them.
An frail, old host would also make it easier to lure in good Samaritans who want to help them; Riot, who doesn't follow the same rules as Venom, would have no issue consuming them. Same thing with the little girl.
Regarding symbiote compatibility with humans, it may not just be down to luck that Eddie survived Venom bonding to him when the others. In the comics, the Venom symbiote has been said to feed off of the adrenaline of its hosts; when Venom latched onto Eddie, the latter was in a panicked state from both the alarm going off and being jumped by a rabid Maria, and immediately started running out of the facility and across a field, thus generating more adrenaline for the symbiote to feast off of. This is in contrast to the test subjects that Drake brings in, where the subjects we see are kept in small environments with very little space to run and generate enough adrenaline to soothe and satisfy the hungry symbiotes and let them adjust to their new bodies. That's in addition to Eddie generally being healthier and better-fed than many of the test subjects (one of Drake's scientists mentions that the test subjects have been kept on diets of liquid nutrients prior to bonding; the Venom symbiote driving Eddie to eat as much solid food as possible suggests that this does not satisfy them and may be why the other symbiosis tests kept failing)
Riot stuck with a small girl all the way to the US - because her much smaller body is a lot more low-maintenance, and Riot wouldn't need to feed as much and thus could stay under the radar better.
Venom's decision to defect to Earth after such a short time with Eddie is sometimes considered an example (romantic or not) of Strangled by the Red String, but since it has access to all of his memories, it likely wouldn't need anywhere near the time a human would to get to know him well enough to make that decision.
Not only his memories. Venom's previous host was Maria, a friend of Eddie, giving him a positive view of Eddie even before they bonded. He got to see a homeless woman and a jobless wreck help each other out through tough times and be friends, and Venom describes himself as a runt and a "loser" on his world, so is it any surprise he was touched by the friendship of two "losers" and realized that's better than what he had on his world?
Eddie is also a rather heroic character at his core. He cares about his fellow human beings, wants to be the voice for those who have no voice themselves, and take on the bad guys no one else will fight. It's easy to miss beneath his bad-boy veneer, but Eddie is deeply, almost hopelessly, idealistic. Sharing that idealism with Venom likely affected the symbiote profoundly.
This idea makes sense, keeping in mind a theory in the comics that the Venom symbiote was corrupted by Eddie's hatred of Spider-Man when it possessed him, only this time, Eddie's idealism turned the symbiote into a better person.
Venom's threat to leave a robber "rolling down the street like a turd in the wind" becomes a more logical threat when you take into account just how steep the streets in San Francisco are.
The bike chase scene ends with Eddie saying “That was pretty cool actually, not gonna lie.” Later on, it becomes known that Venom was a loser on its homeworld. Hearing someone calling it “cool” causes Venom to mess up momentarily, causing Eddie to get hit by the car.
Venom's line singling out Eddie's liver as tasty makes sense, since Venom's probably had enough time poking around human insides by now to identify the one human body part able to regrow itself. And although it doesn't necessarily apply to Venom's nutritional needs, the liver in most animals is actually so nutritious that it's often the first part predators go for.
Fridge Horror
Of the Squick variety: Venom ending its threat to eat a thug's arms, legs and face with the phrase "like a turd in the wind" could easily be interpreted as hinting that it'll eventually eat the rest of the thug and defecate his remains.
At one point, when Eddie is at his absolute lowest, he's standing on the Golden Gate Bridge, looking over the rails, contemplating an engagement ring. He's lost his job, been completely blacklisted, utterly rejected by the woman he loves, and sees virtually no way out of his situation. The scary part is that the Golden Gate Bridge, amongst other things, is one of the most popular suicide destinations in the world. Just how close was Eddie to taking that plunge?
Considering that Eddie's comic book counterpart's reason for going to the church where he found the Venom symbiote was to apologize to God because he was about to commit suicide, its likely that this Eddie was very close to taking the plunge.
Venom killing Carlton Drake, in the end, may have just spared him from an even worse death. Riot was planning to take him into space with a limited food source, and we've seen how quickly Riot goes through its hosts. Now keep in mind that they were going to bring an army of equally hungry symbiotes back to Earth, which could take months.
The fact that Eddie is okay with being a cannibal. Makes you wonder if the "food" is going into Brock's body or the symbiote's. Given that Venom refers to eating people as "fuel in the tank" and Eddie as his "ride" within the same scene...
Eddie: Ugh, god.
Drake killing Dora Skirth. Her poor kids are now possibly orphaned.
Imagine if Daniel couldn't stop the restaurant manager from calling the cops on Eddie when he acts out in the restaurant. In all likelihood, he would be arrested for public disturbance and vandalism. And the SWAT fight scene shows that Venom has no qualms about attacking police officers.....
What happened to the little girl that Riot possessed? How would the parents react to their little girl being missing (and possibly killed??)
Considering that the little girl was with her parents at the airport when Riot took her and we never see them again, it implies that they may have been killed off-screen.
