I didn't think anybody actually DID the virgin endings? Why? Why would anyone playing this kind of game want to do that?
Now, I perfectly understand why virgin endings are included. It's a psychological thing. If the heroine is destined to be turned into a fucktoy no matter what the player does, then they're just a passive participant, but if a "virgin ending" is possible, then the main character sort of has herself to blame for all the fucking she has to endure, and the player also feels responsible.
But... it's like a gun hanging over the mantepiece. It's there to suggest it could be used if the owner wanted to, but why would he want to ACTUALLY use it?
Personally, I always do a virgin run ending first if possible, because I have an overdeveloped sense of empathy. I want a good ending, so I give it to them, then do the corruption/bad end run. This gives me a nice separation in my mind between the 'good' ending that I already achieved, and the 'bad' that I am inflicting upon the characters.
That's just me though. I'm literally incapable of making the evil/bad choices in video games unless I already have a complete good run so I can think of the evil run as non canon in my head. It's annoying at times, but what can you do.
Another reason, and one I think more people can relate to is just an achievement thing. If it's hard and difficult to do, some people are going to want to do it just to prove that they can. I fit in here too, especially because some games with a virgin end have new games plus modes, with the implication that you can start again with bonuses from your first non virgin run to make getting it easier. I make my own life harder sometimes by making myself do the virgin run first, before I have those bonuses, but hey, I can brag about managing to do it afterwards on forums like this.