Billy insists that Gandhi was wrong about an eye for an eye leaving the whole world blind, saying that when all was said in done, there'd still be one guy left with only one eye because the last blind man wouldn't be able to find him to take out his eye in revenge. As they say, "In the land of the blind, the one-eyed man is king."
The scene in the credits where Zach threatens to kill Marty over not putting in a message to Maggie IS that message to Maggie, which is the real reason Marty's not dead.
