Not sure, had the same problem myself on a few occasions. Had them scratch, move and even break some. Also had bears rip the foam out of 3 of my loggy bayou treestands and shred the foam up into a thousand pieces. And had 1 bear climb a big pine to rip the seat out of my api hang-on stand and bend it. Don't know what it is with the foam either.
Ive had bear on every cam i put out this year. Luckily none of them were damaged to bad but without fail i get pics of bear mouthing the cam or face to face with it. Funny about the stands my brother has had that happen too.
I was at Cabela's about 2 years ago and looking at trail cams. I noticed there was a small group of guys listening to a man talking; it turned out he was a representative from of the trail cam companies, think it was Moultrie. The bear question came up and he said always wear gloves when touching your cam. He said it's your scent and oil off your hands that draws them to the camera. I once put a birdhouse about 10' off the ground in a pine tree that I could see from the cabin window. A couple days later I see this bear walking near the pine tree and then stops. He sticks his nose in the air like he's smelling something and stands up for a better smell. Goes straight over to the tree, stands up again and destroys the birdhouse.