Had some swinger pals tell me some wild stories about porn theaters a while back. They were kind of hook up spots for semi-public sex or to meet and go somewhere else.
Never went, as already meeting at the swinger club, but seemed interesting from their stories.
Seems like it's worth a look to check out and to see if some of the stories could be true. Especially considering that people could just watch porn on the Internet or buy a DVD, so logically it appears something else is going on.