What's weird?
You have to pay tax as a ski instructor, or as a music teacher. But as a ski instructor, your tax takes out of your $10/lesson base pay. As a music teacher, you get your tax taken out at say, a $20/lesson base pay. Who gets to keep more take home pay?
If music teachers get to take home $10/lesson AFTER tax and overhead, it's significantly better than ski instructors, who're getting paid $10/lesson and still have to pay tax and overhead from that $10/lesson.
Umm, the resort pays the overhead and administrative costs right down to your ski pass. When I was an instructor any additional overhead/expense was a sunk cost because I would have already been at the place skiing during my free time even if I didn't work there.
Music studio or music store is akin to the ski resort in terms of overhead and who pays that cost as well as administrative costs. As for free lance.. when you can teach skiing out of your house or show up at your studen't house to use their lifts your argument will hold water.. or snow..