So then you get bumped and it takes those guys an extra 40 minutes to set up, then 20 to break down...leaving you with a 10 minute set at 1215 when last call is 1230.

That is, if they aren't providing the back line

"OH, well since we already played, we're just going to load the van at the end of our set. Hope you brought your own shit, we gotta go cause work in the morning sorry have a good show, let us know when you want to play again. Our friends all have to get home early, too, so have fun playing for the bartenders."