I think you hit the nail on the head on this one. Of course, one barrier is people finding out. But that can be remedied by traveling. So that's certainly not the biggest barrier.
To emphasize your point, I saw something that really hit home. I was watching a porn video, with a pro porn BBC and a semi-pro/amateur wife. I never knew that she was semi-pro, until a guy on the site told me she was. So here's this woman who's been making porn videos for years, and she had her hubby in the video. (I'm thinking she's been at this game for easily 10 years)
I was fascinated at how she kept seeking her husband's approval during all of this. Her husband was a rock star, and it's by far the hottest hotwife video I've ever seen. It's easy to tell when something is scripted, but I could tell that is was real.
I won't get graphic, but when her husband asked her if she liked what Mr. X was doing to her, her answer was, "Yes, but so do you, right? Don't you like it?"
And of course hubby said, "Hell, yes." Then she smiled and continued.
And this ties into my theory that I've shared with tons of frustrated husbands...
A wife is much more likely to cheat, than do this with their husband's blessing. Both of these things go against societal rules, but I guess cheating is the lesser of two evils.
