I'll share just a few. We see guys doing that all the time, and we don't even bat an eyelash. As far as I know, a man does not have more saliva in his mouth than a woman does. The only reason, then, that men spit in public is that society allows them to do so. Second, girls are able to hug each other in public.
Some guys hug each other, but it is a very rare event.
I guess they are afraid of what people will think if they express any feelings for another guy. I've even noticed recently that a lot of guys who go to the movies together sit with an extra seat between them. Some claim they sit like that for more room. Somehow, I bet it has something to do with what other people will think. Living in the south, we do see older women who enjoy chewing Red Man on a daily basis.