Sure, plenty of the more avid users in the Ask.com community are a bit older then 15. Some may even be in their 20's (Gasp!). You do get a lot of childish comments, but overall we have a good group here.
It make you wonder sometimes. Yes, I'm over 15 thank God, but one of my favorite quotes is "Growing old is mandatory but growing up is optional". I just don't like the "optional" when I'm trying to get intellectual comments & questions.