It may be social conditioning that accounts for why so many do shave, and why some of those feel they have to. But it doesn't then follow that all people who shave do it because of social conditioning.
People have a variety of reasons, and there are logical thought processes that can lead to shaving down there.
For me personally there were two things which lead to it, and I'll grant you it started because of outside influence.
When I hit puberty I started shaving my legs and armpits, this was because of social conditioning. But here's where it breaks away, I discovered I liked the feeling of shaved legs, and as I'm a very tactile person I then moved on to shaving my arms (to get more of that sensation). I didn't know anyone who shaved their arms back then, and actually got some very strange reactions to it. If I was doing it because of what people thought I'd have stopped it right there. 
From there I (logically) thought, "well if hair free legs and hair free arms feel nice, wouldn't hair free genitals also feel nice?"
Running concurrently to this was the fact that I got a lip piercing at the age of 18. This was due to outside influence because of being in the alt scene. From there I got a variety of other visible piercings. Which, of course, led on to hidden piercings. Including a genital piercing. To me it made sense to be hair free around the piercing to save me from things like getting hair caught!
So the two different thoughts led to me being hair free.
Not done because of what any men want. Not because of what is in porn (I hadn't seen any porn till after I started shaving/got pierced).
As you can see it's not beyond the realms of possibility that some people might have thought of shaving without it being due to conditioning. People are totally capable of independent thought.