My wife does the EXACT same thing when she runs. We live in a gated community with a security guard, but that is really a joke. Pulling in and waving to these folks will get you buy without so much as a glance 99% of the time. I've tried to express to her the danger in running and being, for intents and purposes, deaf, from just cars and trucks that travel the roads, to say nothing of anyone with ill intent.
She thinks I'm paraniod. My fear is that something bad will happen and there will be nothing I can do about it. So, yeah. Folks apparently have little or no care in their environment and the potential for bad things to happen.