I've never been a dance teacher, but I am a teacher. My first post was a pretty lowly one, too--ESL (English as a Second Language) teacher. A significant fraction of my classes were purchased by international corporations that wanted their C-suite executives to be competent English speakers. Which is to say I've been in exactly this position; teaching a skill at which I am extremely competent to people who often have lukewarm interest in mastery, when I earn peanuts and they seem to be awash in cash. Furthermore, my employer is a school that takes a hefty chunk of my earned income without providing services that seems to warrant it (or so it seems to many).
I'm just one person with one anecdote, but I can honestly say that the disparity never bothered me. It's common knowledge (in USA culture, anyway) that teaching is a significantly underpaid profession, so nobody goes into teaching just for the money. That's what Economics (hedge fund management) and Engineering are for in my cultural circles.
Because of that, I've only seen three reasons that people end up teaching.
- They love teaching for its own sake. Sure, it would be nice to also make money doing it, but given the choice between teaching and earning peanuts vs. doing some drudgery that earns well, these folks would rather teach.
- They love the skill, and teaching is their only way to use that skill as their career. These folks are mixed. Some are grateful to be doing the thing they love, and have the same attitude as above.
Others are indeed resentful. Not because of the money per se, but because they feel they should have "made it" as a practicing professional rather than as a teacher (in most of the arts, the vast majority of professional practitioners are no better off than teachers financially, so money is still not really the problem). These people tend not to stay in teaching very long; they discover that they are much happier with a predictable day job that gives them lots of free time to practice and pursue the skill on the side.
- They want to use teaching as a vehicle for having an adventure. Whether that be to have a long-term, subsidized vacation in a foreign country (common among ESL teachers), meet a whole bunch of interesting people you otherwise wouldn't, or just generally experience another face of humanity, teaching a niche skill (one that doesn't require a teaching credential) is a pretty good way to do that. These folks are grateful for the experience also...but they don't stay long in the business, either.