I think things like this stand as further proof that we're becoming an insanely fear-based society. I understand that the intent is to keep children safe from predators, but it fails in it's execution. As an adult that's chosen not to have children, I should still be able to go take a walk, sit on a bench, or even swing at my local park without having to worry the cops might show up. But no, let's just keeping passing more and more vague laws that alienate us from one another and spread fear. It seems like such a 'slippery slope' to me...next thing will be having separate "adult" and "families only" parks, water parks, etc. with cops standing at all the entrances checking ID's to make sure.
The fact that a group of a few adults (that were obviously part of an event) coming in to a public park, sitting on a piece of equipment to take a photo for said event, then going down the slide and leaving warranted dirty looks, calls to the event organizer and the parks department, and apparently quite a bit of internet research, is just painful.