Do a google search on ELF and ALF. I work in law enforcement and know they are active in southern IN. I know you are a ways from Bloomington but that is a hotbed for them. More then likely it is either somebody who lives close by the area. There are some many places to hunt from these days there would be no reason for a person to travel a long distance. It was probably somebody walking around, saw the stand, and decided to do the deed. As mentioned above I would report it to the DNR in that area, you never know you might not be the only victim of this in that area.