IME employee "shrinkage" has less to do with opportunity (remember, employees know the security posture of their workplace; if the public has access, engineering around them is not difficult), and more to do with motive. That is, shrinkage increases when employees are underpaid and disrespected. As is common everywhere, observation of arbitrary rules is down to the push-pull of saving face vs survival. So the issue is not the purported exceptional criminality of low-wage workers, but the low wage itself.
The aforementioned security posture is also often misaligned. I've worked at a warehouse where the only things that could be stolen are fill hoses and washing machines. Clearly, no one was walking out with anything of significance, but we still had to empty our pockets and step through a metal detector every time we hit the floor. Meanwhile, thousands of dollars of easily-pocketable personal electronics disappeared from another warehouse; no metal detector.
The aforementioned security posture is also often misaligned. I've worked at a warehouse where the only things that could be stolen are fill hoses and washing machines. Clearly, no one was walking out with anything of significance, but we still had to empty our pockets and step through a metal detector every time we hit the floor. Meanwhile, thousands of dollars of easily-pocketable personal electronics disappeared from another warehouse; no metal detector.