I don't see the need for a fake name, but I have nothing to hide either. I would imagine in some cases you may want to be as secret as possible - guy might be overly paranoid that a SP might shout his name out in public if they ran into each other, or it's part of the thrill to "be" somebody else. Maybe 'Perry' has always found his name unappealing, so for an hour he can be 'Roch' the sexy fuck machine instead.
Personally, I don't care much for my own name but I use it willingly, nothing to be afraid of. I don't like it being used during sex EVER. You can call me baby, honey, sweetie, cutie, dude, pussymaster....whatever, just don't throw my name out there. I always hated the thought of it with SO's but never had to deal with it. But I had a SP one time ask me all embarrassed on her 4th or 5th visit what my name was while we were chatting. I didn't take offence that she didn't know it at all, but when she used it during sex....I told her not to do that ever again! I don't know why it bugs me so much, I think it's a bit fake to begin with because me or my SO's never called each other by our names ever anyways. And in that situation where it was obvious it was being thrown in as an 'added bonus', it made everything seem contrived.
So take note of that girls, don't use my name! I would rather be told to 'lick the dirty fucking toejam from between my nails you dirty fucking piece of shit' than hear "Oh, Perry!" And that's saying something since I'm not into the being abused thing, nor is my name Perry...