no one was actually making fun of the movie. They're at the stage where they've just seen the movie and enjoyed it so much they just want to quote bits. They're also drunk enough that falling down a landing ramp is hilarious. Most things are hilarious. Consider this: between the numbers one and ten there are only three that start with the letter 'T'. Is that funny? Are you doubled over, gasping for breath because you're laughing so much?
Then you're not drunk enough.
Oh, and Hoshi does normally play by the rules, especially for honest games of skill. A wager of this nature though is more a matter of pure chance, and she has no problems tipping the scales in her favour.