It is indeed tough to get "fired" from a diner.
LOL! Guess what? If you physically confront one of the patrons it is VERY easy to get fired. Trust me. I've been there, done that. Of course, after I grabbed the obnoxious foul mouthed guy by the collar and pulled him to the door and shoved him out I was applauded by the other workers. I still volunteer to fill in once in a while when they are short of help. Of course, most know I don't take any junk so all is well.