Actors appear to enjoy all sorts of things, that's what acting is about. Actors are performers.
I dunno much about porn, my sister and I watched 'Fifty Shades', on Netflix a while back as we'd heard a bit about the book ("Mommy" porn apparently), and wondered what the fuss was all about. That wasn't real nor was the story realistic imo - but it was very scarey.
(The actors didn't wear crosses or crucifixes - some of the time they wore a lot less than that.)
"Fifty Shades" has about as much to do with the "real" world of Dom/Sub BDSM as "Harry Potter" has to do with witches (there are no wizards) in the real world.
For the uninitiated, in a true Dom/Sub relationship it is the Sub who controls what goes on, what happens and, far more importantly, what does NOT happen.
The Dom and the Sub will agree beforehand on what is called the "Safe" word - a word that would never be used in the normal course of anything that might happen during a BDSM session and, once said by the Sub, all,
ALL activity stops, no ifs, buts or maybes, it stops.
Mr Grey is not a BDSM Dom, he is a sadistic controlling bully and rapist and the writer has no idea, and has admiited so, of what actually happens in a real BDSM relationship but this did not stop her writing two sequals that were equally ill-informed.
Most of what "the fuss was all about" was from BDSM afficianados bitching at the misrepresentation of their particular kink!