Hmmm.
Well, I wouldn't be happy if I found someone sitting in my tripod stand. (That is put there on approval of the landowner) And I would definitely have something to say to the lowlife who I found sitting in my stand.
Those who outright steal stands are merely thieves. Not "hunters," most certainly not "sportsmen."
I see this kind of like parking your car on the side of the road. Because it is there, it doesn't give anyone who happens by the "right" to sit in said car, use the car, OR take the damned car! And I think most courts of law would agree with that sentiment.
People have no "right" to utilize your stand (without permission) than they have a "right" to use a vehicle left parked.
If regulations state that a stand/blind etc, is to be removed when not in use, then such equipment should be removed. This is kind of like parking in a "no parking" zone.
While you may be fined, or your stand impounded by the "authorities" it does not give others the right to use, or STEAL your equipment.
If a person believes that a stand/blind is in violation of regional laws, then they must report such a violation. But it doesn't give anyone the right to steal such equipment.