All major swing conventions are couples only for these reasons. The vast majority of couples are simply not interested in single men and to encourage more unneeded males to participate is, in my opinion, a big disservice to the majority in the Lifestyle. That is not what many swinging couples want. A single male has a very different agenda and issues than couples. Many couples have told me of terrible experiences where they bring in a single male for the women, and he falls in love with her and is devastated when he can't have her more often.
Some single men tend to attach like a octopus out of desperation.
Couples want to share as friends, intimacy with other couples without any need to be jealous since they are centered in the prime relationship. Many swingers are looking for much more than just recreational sex, but intimate friendships with other couples. We don't care, we aren't interested, you've missed the whole point and purpose of the alternative lifestyle. In fact, by single guys constantly trying to convince us that they are worthy of a second look, they perpetuate their own misery. Also, I'm sure that the next post from some dork will claim that they've had relationships with lots of couples.