That is absolutely horrible! I can't, and at the same time can, believe that there are people out there who let their children behave like that.
I don't have kids but I'd like to think that I have the respect for other peoples property and the situational awareness to never, ever, let my children do something like that.
I would have been punished if I ever tried that sort of thing.
I don't let my kids do such things, I think it is kinda rude to let them for the reasons you mentioned. But really, they don't do any damage. Apparently, kids think scoots are pretty darn sweet.
I've asked lots of people at Bike Week with scoots if my kid could sit on saddle up. They've always said yes and are happy to show off their ride. I think the asking is the important part. HA!
I've told the kid wranglers that, for safety reasons, it is prolly a bad idea to let their charges run amok. However, I haven't had the heart to usher the kid off if they're having fun.
I'm growing the scooter community from the grass roots!