I'm hoping this was cut off from a longer email, but if it was not she probably could've at least expected the parents to apologize on behalf of their kid, ensure they spoke to their kid about why it's inappropriate to hit people, probably have the kid apologize, and depending on some other factors offer some kind of compensation for the glasses at least as a token gesture.

If your kid hit someone in the face hard enough to break their glasses and your only response is maybe they were hungry here's how I can address that, I can potentially see why they might have done it in the first place.