But to address your argument: you missed the "opportunity" bit. If you're a well-off, well educated person you can choose to do whatever you feel like and I'm sure some people do without worrying about money (perhaps they have lots already). Most people will chose the best paying job that is available to them. Sorry, but reality is on my side on this one. Go visit a factory if you want to see if people want self-realisation or money to survive. Again: please remember the "opportunity" part. If you tell a factory worker he can earn 4$ an hour assembling landmines or 2$ an hour assembling asthma inhalers I will eat my hat if they don't go with the money (and I wouldn't blame them for this).
I didn't miss the opportunity bit. It seems your logic there is backwards: It's precisely if I can choose to do whatever I feel like that I have opportunity, and precisely those people you agree may have other goals than maximizing profit.
Sure, if you have no money and have an "opportunity" to flip burgers, most people would take that job even if they were vegans. That's survival, but I don't think that says much about what they would choose to do.
A better example I think is when people decide to go back to school because they've realized they only get shitty jobs without education. In that situation, they could choose to do whatever. Do most people find a list of best-paying jobs and pick the one at the top to decide what they should study? I think they do not.