Why do single men pay more to get into adult clubs (sex clubs, swinging clubs, BDSM clubs etc)? It's hard to argue against the conjecture that it's to do with supply and demand; I'm sure that many more men would want to attend such clubs.
Some say that by making single men pay considerably more you're restricting their numbers, and that this is a good thing because men are more likely to disrespect boundaries. On the whole, I agree with the premise that you're more likely to come across a badly behaved man than a badly behaved woman and that having more women in a club is likely to modify that behaviour.
So why not restrict numbers? By making men pay are you not increasing the chances of making more men feel entitled to sex? Are you not making men feel relatively cheap and worthless? It really hurts and is hugely offensive to be treated like this (but tough shit, right? Men are to blame for this after all).
Thank you to those clubs and events who find a way of admitting men that is safe, enjoyable and fair for all. I'm sure it isn't easy but, in my experience, it is possible.