It happens with my daughter too, but she is also tan complexion, she has braids, she is a mixed american, hispanic and black, and where ever I go, people want to take pictures of her, and that is fine with me, because they ask, but I taught my daughter to speak her mind if she doesn't like it, so if she doesn't want that person touching her hair, or cheeks or kissing her, she will tell them so.
It can be embarrassing sometimes, but its her feelings.

I don't know if they mean good or harm, But I don't want to find out either.

And it seems more innocent coming from a kid than the parent.