Many, if not most, people would not call any of those fields hard unless they were forced to practice it. A classic example is teaching, where some people seem to believe that bad teachers are bad because they are lazy (not that it requires skill). Even with law, those who claim it is hard focus upon the environment rather than the practice. (Law school is hard.) Pianist, there is lack of jobs. Baseball player, some may regard the training as gruling but not the game itself. Painting, a common excuse is a lack the creativity. Accounting, is seen as boring. Working retail, is regarded as being below them. Writing. Well, many seem to think it is easy yet few follow up by getting published.

Contrast that to STEM disciplines. Not only is getting there seen as hard, in the you need to be inherently good at it sense, but the practice is seen as hard, in the it is not worth the effort sense. On top of that, that accountant may take up baseball or painting as a hobby recognizing they don't have the ability (nor need the ability) to work hard since they will never practice it professionally. The majority of people who pursue STEM as a hobby already seem to be in STEM professionally.