My day job is programming. My "hobby" is learning more about programming, writing about programming, and so on. In fact, I frequently tell people that I'd be programming even if I didn't get paid for it.

Guess what I'm getting at here is trying to determine just how many people don't have a hobby because their work is their hobby?

Or side hustle, for that matter. Plenty of creators on YouTube and Etsy making things. Are they "hobbyists" who've turned their hobby into a hustle?