First band I thought of when I saw the thread title.
I saw them twice in two days a few years ago, at two different venues. Drunk on arrival for both shows, and drank during their sets. During the first show, they were so angry at low attendance and lack of reaction from the crowd that a couple of the band members left mid-show, stole patio furniture, flower pots, a grill, etc. from a house nearby, then came back inside and threw it at the attendees. The audience thought it was part of the fun (like the back and forth hail of garbage at a GG Allin/Merle Allin and the Murder Junkies show) and threw pieces back at the band, enraging them. They jumped down and started beating people up. The venue owner ended up losing quite a bit of money on that show, buying new furniture and stuff for the neighbor. A few of us stuck around to back up the owner when he refused to pay the band.
The second show at a different co-op venue had virtually no attendance (word spreads fast in the local all-ages scene), with only co-op members and volunteers there, and one of the band members took a swing at the guy who was running the venue that night. Most of the members and volunteers were there because of their behavior the night before – scene police, essentially – and we chased them out. The venue was on eggshells with the neighborhood, with regular harassment from local police, but for once we were glad to see the cops in the parking lot… “hey, those guys driving away are really drunk!”
Another pretty offensive band: The Mentors, lead by “El Duce,” and their self-described genre was “rape rock.” Saw them once, too. GG Allin seemed like a kind of performance artist specializing in offensiveness, but El Duce was just depraved. A continually drunk sexist pig of a man (which may have been an act, but seemed to be genuine), who didn’t seem to be joking when he would talk about how he could tell when women wanted to be raped, and so on. An example of some typical Mentors lyrics:
“I know I´m just a bum
Beat your ass just like a drum
Listen bitch, do as I say
Service me or be smacked
I can replace you some day”
I do have to admit that seeing him sing that kind of stuff at a riot-grrl-friendly venue was entertaining. They left the stage with fewer working amps than when they started. 
El Duce died from getting hit by a train while drunk.
