I can't remember which department, but I remember the local SF/Bay news many years ago talking about some supervisor at that department somehow making $1.5 million the year before (or something insane like that.) They explained how it was all possible, which to me seemed like he had just been with them for so long, he knew exactly the optimal way to play the system and exploit all the loopholes in it.

As for your second part, I guess it would seem unlikely for some positions, but I know a doctor who made like 3x his base salary each year through all sorts of absolutely legal, ethical, and hospital-sanctioned means. Taking every single weekend he could on call (even offering to "relieve" other doctors who had been assigned that weekend) for example allowed him to make much more than you would ever think possible.