But work is work. If you're doing it for the benefit of a business only because they're paying you to do it then that is the literal definition of work. Just because it's not hard work doesn't mean it's not work?
Besides, that number isn't self-reported numbers, it's from a study I read recently, and it was included as a tangentially related point. I could try and track it down if you like.
It's also important to note that not every CEO is a billionaire of a megacorp. There are millions of small business owners who are also CEOs.
I actually love my job as a software engineer! I'd rather do absolutely nothing else, as a boring desk job where I sit around looking busy all day would bore me to hell and I'd very likely make 1/3 what I'm making now. I find exactly zero interest in a "people job" even if it paid more because I wouldn't enjoy it.
So, the reason I do the job I do is because of personal fulfillment and money. Beyond the bare minimum of survival, that's why people do the jobs they do. It's not rocket science