I appreciate the feedback so far. I am not all that worried about personal safety at this point since they are after easy to steal stuff. I don't think this is much different than the people who steal bikes from campsites and whatever else. I don't think this campground is alone in this kind of problem, and I am not ready to give up on it yet.
My aim is to dissuade them from poking around at all. The easy part is to minimize the goodies lying around that might interest them. The other part is to deter them from looking around for anything I might have missed. I think the motion light is one thing, and I like that perimeter alarm that will alert me and I can turn on floodlights remotely to deter them (and ID them).
When this happened we had another night to stay, and I couldn't decide if it was better to leave the lights on or turn them all off that last night. That sort of led me down this road of trying to figure out how to make the area a bit more secure. Has anyone heard of any camera systems that could apply? I was thinking of getting a couple of those dash cams and just pointing them out a window to record the goings-on overnight, but something that broadcasts to a smartphone would be even better since I can just sit inside and watch. Probably will just end up being bears going through the trash, but it would be good to know that as well!
Andre
PS I'm okay with guns, but anti-personnel mines is a bit too risky. I'd forget to disarm them in the morning and the kid would have to cook his own breakfast.