So there is some amount of needing to do something you don't necessarily love for a job, but it's perfectly reasonable for you to also not want this to consume your life 24/7. I mean, if you can achieve the feat of the photo at the top of this article—getting paid to surf—that might be great, but that's not really the norm for jobs.
Commissions really suck sometimes, as they aren't creative and generally aren't enough to live on. Comic book artists often work long days only to be greeted with pain at the end of the day. Hand cramps are the least of the worries: such artists often develop problems with their dominant arm, commonly carpal tunnel and tennis elbow. And these are usually contract jobs with no benefits whatsoever.
My mother is an excellent seamstress. Most paid work is wedding alterations, tailoring clothing, and sewing patches on military uniforms (decent demand here for quality work, which she does). That work absolutely bores her and she winds up hating her hobby.
Of course, these aren't exactly in demand per se but is illustrative of how things change once you are working for it. It really isn't all that easy.
Another way of looking at this is: rather than basing your enjoyment of life on pursuing a pleasant hobby (which you may or may not be able to get paid for), instead derive your enjoyment from doing things that need to be done.
In our society that translates roughly to "earning a living by helping others". If this is your source of satisfaction, you don't need very much luck.
When I was first looking for a job out of college, I asked a couple of area technology companies if I could work for them for free. In both cases they told me that their corporate / legal policies wouldn't allow it.
People also don't understand how many free hours those people had (because a lot of farm work is seasonal).
I disagree with this. I'm simply unhappy working on any single thing for too much time, no matter how fun or interesting it is. It's having a few things going on simultaneously, and being able to switch between groups of people to interact with (where the null set is also one of those groups), that has always kept me happy.
Sometimes it's as simple as being tired of being around people, in general. Balance in this case means having some alone time. Sometimes it's just being frustrated and tired of computers and the internet, in general. Balance in this case means getting out and going on a weekend trip to a national park, away from internet access. Sometimes it's that you enjoy your work but you don't enjoy the way people at work treat you sometimes. It's not a dealbreaker or showstopper, but you need time with those few close friends that you feel comfortable around.
It's especially true when you work on a startup or anything else that necessarily involves not being your true self. I spend most of my working hours being what my teammates/investors/customers want me to be, not being myself. That doesn't mean I'm unhappy working on that focus, it's just mentally tiring and exhausting to deal with what's involved in turning that focus into a company.
I spend the rest of my time being my silly self and let my imagination run wild and invent freely without dealing with people, law, ownership, money, or any of that nonsense.
None of this means that I don't enjoy what my main focus is.
'Balance' in this respect doesn't mean 'give equal energy to work and play'. That's what the article is wrong about. 'work-life balance' means 'don't let work take over your life', which many people do. If you can sustain yourself by doing your joy, then 'work-life balance' is a meaningless phrase for you, and isn't intended for your consumption.
It sounds like they made a bargain[0] with "Phil, the Ruler of Heck and the Prince of Insufficient Light."
[0] https://ic.pics.livejournal.com/icon_uk/11800056/855574/8555...
If you're not happy with whatever your main focus is, you need to change it, not add more stuff to compensate.
(Of course, there are still some things that you should pay attention to apart from your main focus, like your health and family. This is not the point here).