my friend had a hookah, and the nice ones do cost a fair amount of money, so it seems reasonable to rent one especially if you don't smoke it that often, plus it comes with tobacco and coals(both of which cost cost less than a couple of bucks per bowl but w/e). as for smoking illegal substances, we tried that in his hookah, but its difficult to pull off. first of all, all the tobacco is in molasses, and a lot of the smoke comes from that molasses, which is what gives the flavor. So in order to smoke anything else in it, you need something thats close to the same consistency, and even then, i would much prefer a pipe or water pipe.
ps. butter does not replace molasses