If they have a hand crank they can raise it but it is going to be a lengthy job and take awhile.
I have never heard of one being stolen and I not going t worry about it. They would have to have a vehicle setup to haul it and there isn't to many people in the middle of nowhere that is looking to steal a camper. Crooks are going to work in heavier populated areas. More chance of finding something worth stealing than in the middle of some woods.
It would be easier to steal a 5er or a bumper pull trailer. Also a MH. With a MH they wouldn't even have to have a rig at all. walk up and hot wire the MH and drive off.