At the end, Curly and Laurey get married and the characters literally sing the praises of their soon-to-be state, declaring it to be a place of natural beauty, agricultural plenty, and boundless promise. Which becomes very ironic when you realize that the Dust Bowl will happen within the happy couple's lifetime.
Not to mention the absolutely brutal weather that the state experiences on a yearly basis. If Oklahoma is famous for one thing in particular, it's tornados.
When you add the troubled history of the Oklahoma territory before the area ever became a state, it gets worse. The entire territory was one big reservation before it was opened for settlers. Thus, the absence of Native Americans is quite jarring. The farmers and cowboys celebrate the new state of the Union, but considering the entire Trail of Tears story, a big Values Dissonance occurs.
There's a reason why most Oklahomans have little love for the film (in addition to their dislike of the attempts at an Oklahoma accent).
Curly hired the surrey for the Box Social. The wedding happens weeks later according to the dialogue. So why is it available again for the closing scene where the suggestion is made to take the couple down to the train in "Curly's Surry"?
Maybe the town decided to hire it again off-stage.
