THC isnt water soluable, bongs don't lower the amount of THC, but they do take out some harmful toxins, which add to the heavy feeling you get in your head and ears and shit. Bongs give you a "cleaner high" then bowls and blunts/joints, so people that associate being high with that thick-headed feeling probably wouldnt like bongs as much because it takes some of that away, some peeps prefer blunts because the leaf is tobacco, and nicotine is a drug, and mixing drugs is always better. (ok, not always) Just like some people like smoking a cigarette to "add" to their high, but I would never tarnish that "oh so lovely" taste of the great green herb.