A lot of people only seem to be grasping the kids section of the "not allowed in the city" part. Teenagers are also a part of that. Not that it changes much really since kids are still banned (I personally don't view teenagers as kids and when I was a teen I dispised being viewed as a know nothing child).
Anyway, sure I would give it a shot assuming I wouldn't be (see what I did there?). For some reason I see crime being bigger in a place without kids... Not sure why. Being that I work as a retail cashier+bag boy simulationously, yes, small childern and snobby teenagers are factors I wish I didn't have to deal with every day. Are they all like that? Of course not, I've had quite a few sweet, well mannered kids and very polite and respectful teenagers that I've had the pleasure of actually having a conversation with (having an actual conversation with anyone is a feat). So it isn't because I think "All childern and teens are mindless beasts", goodness no. It would sure be worth living for a while though, plus, there is nothing keeping me there so when I decide to start a family, I can leave.
Short Version: Yes, I would live in a city without people under the age of 18.
EDIT: Also a bit surprised by the poll's turn out so far. (No spoilers, vote to find out

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