What are the damages for getting booted off an airplane? A few thousand dollars? What happens if you get your head busted up on the way out? Maybe $50k? The only attorneys that would take a case like that would net you pennies on the dollar after fees are taken.

It's a few hundred k probably - juries hate airlines :)

Most attorneys have no problem taking these cases.

Also note that once it's clear it's not legal, the police/city also can be sued if they intervened.

Part of Dao's settlement was an agreement not to sue the city of chicago for that reason.