Memes

The equipment usually isn't sized for adults. I barely fit into the swing set at my local park, and I'm smaller than average. Even though I can technically use it, it's very uncomfortable.

But besides that, as a grown man I'm going to get some very weird looks from parents if I waltz up to the jungle gym and start climbing with their kids. There may not be a law against it, but it's certainly not socially acceptable.