Exactly! Warn a thief once and make it clear if they are caught doing it again a load of buckshot will be liberally applied to the bridge of their nose. Word will get around. Theft will slowly taper off at first until thieves realize that this is for real. Then it will come to an abrupt stop.
Except for a few diehards who will tempt fate.
“Warn a thief once”
No warnings. Raiders know they are raiding.