I like how little kids are made out to be the only ones to play, "make believe".
I know adult leaders who claim more, lie more about themselves, and retain a much lesser grasp on reality than my youngest member.
Keep that in mind while judging the younger members and the covens they are welcomed in. I for one, am offended by this on a personal level regardless of whether or not you meant for it.
So yeah, check out the rest of the covens and get to know the members before deciding this place truly needs a coven for "adults".