The guy is an idiot. Choices are one thing, but the child is too young to make choices for herself, and he is obviously too stupid to make them for her. There are probably laws already in effect to cover this. Just like the laws about kids and seatbelts, there is probably a law about kids and bikes. Might be something to ask in case you see the dork again.
That don't fix it? Get a bigger Hammer
1993 GSXR 1100