I found one on public land last year, only problem with that is you have to go through my friends place to get it and he was with me, he took it down and I kept it. Not the nicest thing to do but trespassers don't deserve to keep their stuff
I have that problem pretty much every year. We've got a large section of public land landlocked and it never fails that people find a way onto it. The majority of times the cams are set up on feeders with stands set up (which, the feeders and stands left over 72hrs are illegal here) because ppl seem to think that no one can get there to check up on what they're doing. I won't take their stuff, but their SD cards get handed over to the game warden.