Passion won't drive you through a decades-long career.. it will definitely get you motivated at the start to work hard, but if you don't get affirmation and reward for it, passion will die out.

This is human. Not unique to teaching profession or any other profession where people complain about lack of advancement. Are people greedy, money-faced when they do that? Not always. Sometimes it's just human nature to want some reward for hard work and achieving results.