Your theory doesn't tally with the amount of reported theft (Only know from my airport obviously) with the huge amount of padlocks collected.
Padlocks could be twisted off, and the chaps knew how to drop the integral lock types in the right way so as to spring the locks
This alone shows that the locks are not up to standard.
FOD on the ramp also includes...Case handles, Baggage labels (Leather and plastic types), Metal case logo's, Baggage straps. (Tie them don't click them), Case 'feet', etc etc. All from the general bashing they get in transit.
I have no doubt that the odd criminal mind would be working at any airport. However the sheer amount of lost locks means (according to your theory) that virtually every baggage handler rifles bags........Which of course is complete nonsense. If you believe that then give up flying. Certainly take the advice given and don't use padlocks.