Your 10 year old sister can and should be banned til her 13th birthday. She is not allowed on Gaia.
Also, following that, Gaia is PG-13. Cigarettes are perfectly legal game.
Don't like it? Ignore it. Gaia's not going to remove one harmless item because you got a little pissy about it.
Besides, anyone who's dumb enough to smoke because a single item on a forum site made them think it was cool, deserves every bit of lung cancer they get. neutral (IMHO.)
I personally found the description to be a bit of a throwback, to the days of innocence when no one knew about the harmful effects of nicotine, and when everyone smoked because it looked cool.
By the way, Gaia doesn't care if you leave. Your friends might, but as a corporation, one single lost customer out of the thousands gained daily doesn't mean much.