Hmm ... I realize I've posted on this thread before; but it seems I need to repeat myself. Gotta say, though: I think it's weird that this subject comes up under the thread of sexuality rather than some thread like "hospitality", but Oh well.
The first I heard of "couch surfing" was a New York Times article about a nudist (guy) NYC who made his practice of living without clothes clear in his couchsurfing profile. In other words, "You're welcome to stay here. I'm going to be naked."
I see any number of Couch Surfing profiles by gay men who make it clear that they would prefer male house-guests: what's the problem with that? They are not dissing women, they're saying they'd prefer male house-guests.
A gay nudist joins Couch Surfing, identifies himself as gay and as a nudist and says he prefers male houseguests: he's not advertising for sex, he's offering hospitality; but he's also alerting potential houseguests that if they stay with him, they're gonna see some skin: that's simply being honest.
And that gives no one any right to complain.