The parents are to blame . . . . the ones on the audience, I mean.
Why the audience, and not the child’s actual parents?
I’ve been condemned as a ‘groomer’ here, just because I don’t think the kid should be shamed for something adults might see in his performance, but which, at his age, he probably doesn’t understand at all.
For a kid who likes dance so much, there are lots of ways to gently steer him toward other forms of dance - instead of shaming him in ways he can’t understand. He might become fascinated with dance in general; but making him feel that he’s done something shameful is just going to turn him off to the whole thing - and introduce sexual issues that themselves are inappropriate to his age.