I've spent more than half of my life working, I've never stolen from my employer and I don't recieve "truly astronomical amounts" in pay.
A company I worked at, when we got nicer offices that had actual showers, had someone take a dump in the shower within the first month of moving in. I think we were around 1500 employees at the time. It would never occur to me that this would happen, but now I know to expect anything once you get enough people together.