This reminds me of a thought I had a few years ago. A Sheriff in my state was arresting for buying IT equipment using department funds (I think it was Cisco gear) and selling it on eBay and pocketing the cash. He had done this a bunch of times. As someone who works in local government and knows how things work here, my thought was instantly the following:

-> some gear get purchased bet never used/installed for a few years. Sits around gathering dust. -> Sheriff sees this, takes it home sells it on eBay. Nobody notices or cares. It wasn't being used after all. -> Sheriff finds other unused gear, takes home and sells it. -> No valuable unused gear left, so Sheriff starts buying stuff simply so he could take it home and sell it. -> At this point it is noticed. Seriff gets found out and arrested.

If it was just the first step, nobody would have noticed and the guy would have pocketed $20k or whatever, and no one in the world would have been the wiser. The auditors may have eventually discovered the piece missing, but long after any video recordings expired, and the original purchase was perfectly legit. But greed combined with stupidity got the guy arrested.