Eating chocolate chip cookie dough ice cream is perfectly legal, but nobody's forcing you to eat it.
Drinking alcoholic beverages when you're over 21 is legal, but no one here is forcing you to take a swig of beer.
Putting kahlua on your ice cream is legal too, but you don't have to put any topping on there if you don't want to.
Before I stray any further than that, I don't care for marijuana myself, but I support its legalization. I know no one will be forcing me to take up the stuff, nor will I be forcing it upon them. You'll have the same choice not to partake in it, when the day comes that it is fully legalized.
By virtue of somebody else smoking, you're forced to consume secondhand. ---
(\/)(\/)|-| There are precious few at ease / With moral ambiguities / So we act as though they don't exist.