Doing what you love

I read with fascination what Seth Godin had written in his blog lately. Here's one para that I just have to quote:
"Doing what you love is as important as ever, but if you're going to make a living at it, it helps to find a niche where money flows as a regular consequence of the success of your idea. Loving what you do is almost as important as doing what you love, especially if you need to make a living at it. Go find a job you can commit to, a career or a business you can fall in love with."
Some people hide behind volunteerism and claim altruistically that what they are doing is for others' benefit. This does not say if they really enjoy what they are doing. It's one thing doing something to help others but it is totally another to doing something one enjoys while helping others. While I do not deny that it is magnanimous to help others but some actually do it with a grudge. To such people, it is better not to be involved.
On the other hand, it is also unrealistic to do something one loves and disregard the practical aspect of earning something from it in order to survive in this world. So why can't we do something that we really love and let it also help to bring in the dole?
At the end of the day, I suspect that the real issue is with personal satisfaction or the kind of lifestyle one truly desires to have. What are you living for has to be answered with what are you working for?