Yeah I can see your points. One thing to keep in mind is that everyone is different and some of the sites you mentioned are still around so that means they are making money which in turn means many people like them.

Kink makes a point of doing a sort of behind the scene interview pre and post scene. They make it a point to have the girls say what they want the viewers to hear. Who knows what really goes on behind the scenes besides the participants? Nobody does.

My main point here is don't always believe what you see, much of it can be rehearsed and contrived. Much the same as the actual action is.