I wonder how many people stopped and stared at these guys as they rolled around the park for several hours taking a picture every time they moved a muscle. Personally, I would have left them to their business. My mother told me never to hang around with the weird men in the park with digital cameras. I think she was referring to the guys who would hide out in the bushes and take pictures of the swing set, so these guys might get a pass.
Remember, it’s okay to hang out with vagrants because they don’t have digital cameras. If you’re really nice they might show you a dead body or give you a swig from their hip flask.