Stops Catalytic Converter thefts! (inexpensive method)

I'm curious - is the CC on a diesel pickup higher or lower priority for a thief? I heard the CCs on a diesel are less likely to be stolen. But it was never confirmed.

Years ago, we had a ATV stolen during the night while parked at a RV park. They simply rolled it away some time during the night. Harbor Freight sells a "driveway alert" and its cheap. If I had placed it underneath the ATV, they wouldn't have been successful.