All you need is a flashy camera, the bigger it looks, the better! Even if it won't actually make a difference in the photos (I took those photos with my smallest kit).
I haven't shot at a club in some time. Back when I was first trying to get into it you wouldn't find a lot of other photographers at the same venue so it was a good opportunity to learn. Now, you'll find at least half a dozen photographers anywhere you go. They all shoot from some new website and think they know it all.
Club owners and event organizers are already cheap to start with, and now they are even less likely to pay for services considering most photographers are willing to give away their photos for free. What's worse isn't the competition, but that people got used to photographers and now just give you the same canned poses and expressions. It's hard to get variety and true emotions and makes club photography even less interesting. If it weren't for the Halloween theme in the gallery I posted, all the photos would've basically looked the same!
Anyway, here's a pic of me with some nuns: