Male bodybuilders and fitness models do shave (or wax) their pits (as well as their chest and backs if necessary). For contests, male body builders remove hair from their entire bodies, including arms and legs (maybe not 'privates', but they must groom there a bit, because the briefs they wear are pretty skimpy).
If you look at the covers of Men's Health and Muscle and Fitness and other men's fitness/weight training magazines, they are all 'manscaped.' It gives a much cleaner line for showing the muscle. I'm pretty sure the men in STS are fitness models (they were found during a 'talent search') and so they keep groomed for their profession.
I'm not sure, but I think metrosexuals may also shave/wax (they definitely do more 'manscaping' than the average blue-collar worker, and have their backs waxed if necessary).
I actually prefer a relatively hairless look (except on the head!). If a man is too hairy (especially if they have back and/or shoulder hair) it's rather repulsive to me.
