Yeah, over on Pennock's we had a group who would take every opportunity to start crap. There's a rating system in place on that board that is run by the members. If someone begins posting in a manner which starts trouble, i.e. hate speech, harassing other members, post flooding, etc, nowadays they're gone fairly quick. The moderator has the authority to override the system, and allow people back in, but in every instance but one where that has occurred, those individuals got themselves booted again very shortly thereafter.
One of the worst offenders started an anti-Pennock's site, lol.
I noticed Rennlist has a very effective motivator to prevent that sort of thing...they hit 'em in the pocketbook.