Off and on for 20 years. Between various legit jobs, I'd bounce.
Too many dust-ups to mention. Some actual fights, others "skirmishes" (the majority).
In all my time and in all the various establishments I've only been KTFO once, and at that, it was only for a few seconds and from a sucker punch. Happy ending: My partner on the door caught him down the block and literally soccerballed his head off a curb. Ambulance took him away.