Our club, DJs Island north of Pittsburgh, has a policy for single men: You must be introduced by a couple who are members, the first night you must arrive with and leave with them. After that, the single men are allowed to come on their own. Of course, there is an seriously increased party fee for the guys. These rules ensure that the man is genuine.
In years of going there, I can say we've never met a disrespectful single man there. Many chatted up my wife and myself, a few times they got lucky with her. Usually it happened after we'd been in a private room with a couple and while I was sated, she was still raring to go.
Single men who get into a swingers club and then aren't politely assertive wouldn't make great lovers anyways, IMHO.