Gotta love how you solve world's problems in a single blog post!
I'll tell you why people do what they don't love. Because money is needed to sustain yourself in our current society unless you will leave society, go to a mountain top and grow and make everything you need yourself. In fact, this is why saints ditched the mainstream society.. because their interests did not align with the needs and wants of the rest of society. If you look at their lives, you see that they either go to places where their basic needs are met, and they get to focus on what they wanna do... or they end up working at universities teaching, and researching.
Money is earned when you do what other people want. If what you like happens to align with what others like, then you could potentially be a gazillionaires with ease. If not, you are in trouble!
I agree with you that in some cases (perhaps most?), people don't try hard enough to find the intersection of what they love to do and what others need. For example, you seem to have found a happy medium between the two although you still get flamed when you talk too much about what you care about which does not align with anyone else's interests.