If you've got a lot more fights, you have to consider the format that the club plays. Not to be racist, but when you play a predominantly urban format (hip-hop, rap, etc.), you get gangstas, wannabe gangstas, and the associated hos who hang around them in one enclosed area, and it's an easy recipe for fights.
There was a club I spun at a long time ago. When I had the Friday nights, I played mostly house music & upbeat (120+ bpm) Top 40. Didn't have a problem, it was always classy.
Thursday nights, when they played hip-hop & rap, always had fights. When they moved the format to the full weekend (Thu-Sat, mostly urban music), it was the death knell that caused the club to gain a reputation of fights and douchery. The ladies didn't feel comfortable, so they stopped coming, which in turn meant the guys stopped coming, and soon it was only the gangstas, wannabe-g's, and tourists who didn't know any better who came...
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