In the suburbs of chicago there are plenty of fields that are maintained pretty well and not locked. I like most here do not see many kids just doing a pick-up game on their own, however as a kid I never played the number of organized games these kids do today. So they might be missing on some of the fun I had but there abilities are much better.
They throw better, hit better and certainly are stronger and faster then in my day.
I do see on occasion games of running bases, home run derby, but never my favorite, strikeout against a school wall.