Well, I'm not sure that I'd say it's "gay"... unless by gay you mean happy, and then maybe I'd be in agreement.
There are a number of reasons people shave their body hair.
Runners and swimmers (and volleyball players, other athletes, etc) for aero/hydro-dynamics.
Wrestlers to prevent hair from being pulled out
Bodybuilders for show-purposes, and probably also for hygeine.
Hair, as you may well know from that which is on your head, is naturally oily, and, whether thats related to the fact that hairs can often trap odours or not, I'm not sure. However, I think it should be evident from any athlete's experience, that body hair does retain odours, and even non-athletes... does hair not keep a shampooey smell, or a cologne/perfume smell? It does. It also retains the sweaty bacteria related odours, 'body odour' as it is generally called. Maybe he shaves/removes his body hair simply to prevent from being a big smelly man?
Many people I know keep themselves well-kempt 'downstairs' for similar reasons; namely smell, sometimes for appearance, but it largely depends on how much sex you're having and whether that's a concern. Of course, this bodybuilder guy might want to shave 'downstairs' simply so that he doesnt smell of sweaty ass. Who knows.
I'm pretty sure it's not gay, though.
I'm not gonna tell him i think hes gay as he is rather large
