The person who said this article should have been titled "Started doing Marketing for My Passion and It Appeared I Don't Love Marketing" is right on.
I've met musicians who were totally uninterested in going to see anyone who wasn't "happening." You can't blame them, since they're trying to make a living.
I always thought about programming: "I like it OK. Sometimes I like it a lot, but it's a living. I don't do it at home for fun."
If you don't mind writing what sells, then that's a living. F. Scott Fitzgerald tried selling out in Hollywood, but he's not remembered for that non-passion part of his work: