It's always about the money. You don't have to look any deeper than that. Even the zealots and crackpots are paid, and if they weren't, you wouldn't be hearing from them. An unpaid zealot is a silent zealot.
For people who are selling something, it's all about the money. To make more money you need more power, so power is a necessary but secondary consideration.
For people who aren't selling something, it's all about the power - but to get power you need more money. More money equals more power. They chase the money first.
Cigarettes keep you addicted, the tobacco company wants you on cigarette, its always about the money.