[JnCC]

Just let it drop. If they're as conservative as you say, their participation in any kind of alternate sexual lifestyle is attended by a certain degree of shame and embarrassment. There are couples who prefer to swing with people who are, and who will forever remain, relative strangers. As for your friends, you know, they know, and now, you both "know you know." I'd just leave it at that. If and when they're comfortable discussing the subject with you, they'll bring it up. (My guess is that it will eventually happen)

As for why this guy posted a picture of himself in their profile, all I can say is, "people sometimes do things they later regret."

That was certainly true for a former GF and myself. We posted a profile on SN that apparently revealed one too many details about us. The next thing we knew, we had one certain gentleman in our circle of motorcycle-riding friends who told us he "knew all about Swappernet...saw us on there...knew all about the swinging thing...and wanted my girlfriend to help talk his girlfriend into it" We denied everything of course, but he still became a major pain-in-the-ass to us for many months afterwards. Every time we sat down at our local watering hole or stopped to rest in the middle of a ride, he was right there. And any time he was around, the topic of conversation invariably turned to swinging.

I'm not sure how widely our story was repeated among our circle of friends, but I know that putting face pics or any other personally identifying feature in an adult, internet profile is usually not a good idea.