The off-airport HLSs I regularly use when I fly to work are generally pretty quiet spots.
I do a preflight walk around and check that nobody has been loosening nuts and have been lucky so far.
Incidentally the only time I ever had anything stolen from an aircraft (fixed wing) it was parked inside a hangar at a licensed airfield!
I remember a few years ago seeing an ad for a device that involved laser beams and traffic cones placed around your machine and giving you an alert if the security cordon was breached.
Did anyone buy one?
SB