Hmmm....That's complicated. I was at a birthday meeting last night where children of those celebrating birthdays attended, and to me it seemed very sweet. I don't see people from my meetings anywhere but AT the meetings, but it wouldn't matter if I saw them anywhere else(to me, at least). It sounds like the little girl really understands the significance of members being anonymous. If it was me, I wouldn't worry about it. But to answer your question, no, I wouldn't say you are out of line. You have a right to privacy, but maybe just look at this from a different perspective.
As for it being a closed meeting, I think that's always tricky when kids are involved. You're right, closed meetings are only open to alcoholics or those with a desire to stop drinking, but sometimes things can't always work out like they should.
Hope that was a little helpful, and best wishes on your recovery.