my personal stance is they are as bad as heroine/cocaine and all the other illegal drugs, only difference being this stuff is legal so it's "accepted" by society(if some of the illegal ones became legal they would soon be seen as "accepted" within a few years) much like alcohole.
all of these provide either a relaxed/pysiological/mental sitmulant pretty much so that's why people obviously use them, i really don't see much of a difference between any of the drugs anyway. difference being the ones you smoke will kill you slower but generally you can easily OD on drink/injected drugs as people are to dumb to look up the word moderation(you can even overdose on food nutrients but it's much harder)
still if people wana smoke then go for it, you know the risks so you take them like everyone else does with whatever they do in life(moderation should always be the key)
i know people who are hooked on caffiene drinks, health food(its all good to live healthy but its to see when it turns into an obsession) etc, i'm probably hooked on masturbation i could argue given the amount i do it/places i do it.
i only hate that the hypocrosy i see these days of people viewing those who do illegal drugs as the scum of the earth(moderation is fine, crackheads i agree much like people who smoke 40+ fags a day) when they themselves are doing weed/fags because it's ok since they are "legal". that and people who heckle smockers annoy me, specially when i see a some fat person doing it "i'll put strain on my body eating this crap but i'll bitch at you for doing that bad habbit!")
rant over.