Many also supply paid ladies to make sure that the guys who pay huge amounts for entry don't stop going in. They also do things like 'greedy girl nights' and those especially would have paid girls in. I wouldn't entertain a club like that when I was swinging, as I felt that the whole point of swinging and enjoyment was being able to discriminate and pick and choose your victim and sometimes that meant rejection.
The club that I liked to frequent had no alcohol license, which meant the police could not turn up unannounced and it was classed as a 'sauna' as it had 2 jacuzzi's, steam room and sauna as well as the play rooms. So despite no money exchanging hands between two consenting adults, it is still frowned upon and monitored. People just don't like anyone having sex without the grief that comes with relationships, let alone having extra marital sex with your partner!!!