I wondered if that was the case, but having extra discretionary income doesn't explain the dead space between $20 and $100. It's a pretty bimodal distribution, and the directors/VPs aren't all making 5-10x what a mid-level eng does.

They definitely do more communicating and less creating. They also seem more willing to invest cash rather than just time into their careers. I'm sure having extra income doesn't hurt, though.