Free: Contests & Raffles.
Take the head. If a sh!thead wants your animal that bad, he'd have a hard time 'slpainin' ,where's the head, question from the game warden. I shot a 6x5 elk one year and the game warden told me hide the head in camp as best as possible so nobody would steal it.I hate thieves......
Of course "it depends": where you are hunting, how many other hunters are in the area, how difficult it is to conceal the animal, how long you will be leaving it unattended, did others hear your shot, and how valuable it is. Generally speaking I do not believe it is a serious risk in most instances.
In my family we always just make a backpack out of the deer, and pack it out hole, theres been a few that took awhile but we always get them out whole.
Interesting issue... I almost always keep a drag rope in my pack and haul my deer out of the woods right away.
Might think about setting a hidden trail cam by the truck. I've been considering it. And placing in such a way that I can probably get the license plates of any vehicles. I will go out for a few days and be miles from the car. It gets unnerving when you see guys (not hunters or hikers) that look like tweekers hanging out in the parking lots.