> I dare you to try hanging around a school with a DSLR taking pictures of kids in the playground and defend yourself with "But I'm in public."

You'll probably get harassed by school staff and parents, but the police will have no grounds to arrest you.

> If you take a picture, or ten, ostensibly of Times Square, no one cares. You can't piece together a person's day.

Yes, you can. Private investigators often do exactly that.