Aside from the risk of it getting stolen also, I have been thinking about stashing a trail cam next to my rig so its out of sight, but still covers the area around my rig. A flash model would not be wise of course, but mine is the IR model so it would be at minimal risk of discovery in low light conditions.
I really doubt that any of these dirtbags that cruise these areas looking to mess with parked rigs would even consider the possibility of a hidden camera. Hide it good, cover any of the indicator lights that may come on when the sensor is tripped with tape and you may have just what you need for a report if there are any problems while you are away.
Also, would give you a good idea of how many rigs come and go through that particular area/road.