I think if you flip that thinking, there'd be people spreading the word that the prevention is minimal and the punishment not a serious deterrent. e.g., no one thinks "I wonder what happens if you're busted grabbing stuff out of a shipping container?" But if there's no punishment, word would spread fast. "Those guys have been doing it for weeks and no one cares. X got busted but they had to let him off light. They don't do anything about it!"

There's also literal evidence from the original article that these criminals know they won't be punished and can do it with impunity.

That seems likely, but that's existing criminals. Doesn't it make logical sense that lowering punishment enough will attract rational people who are not desperate to do crimes?