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This isn't a guy who was using a skate park and suddenly a bunch of kids showed up. This was a guy who went to a skate park that already had kids using it and tried to ask them to leave.
Seems pretty odd to complain about kids at a skate park. I take the kids to skate parks from time to time, and they are always full of kids. Preschoolers tend to keep to the flatter/gentler areas, older kids do a good job of going around them. It's never been an issue.