I wish there would have been one sane person on that car with a spine.
He could have told idiot #1 to eat with some fcking manners, none of us wanna see that.
He could have told idiot #2 that she is a disgusting fat bastard, and to keep her mouth shut.
Then, he could have smacked down any idiot that stood up and tried to start shit.
Personally, I probably would have busted up laughing if some clown was eating like a slob. it's always best to call out obnoxious people with humor. They realize their behavior is out of the norm, they see you're not scared of them, and others are encouraged to join in on the friendly mocking.
Then again, I also laugh out loud when people fart. I always say "so youre one of those hard handshaking kinda guys" to call out people for being a-holes with the handshake. If you grin and say it loud enough, the slob or jerk will realize you ain't prey, and that his behavior is kinda disgusting.