I'm one of the lucky ones in this industry, I'm sure. I taught full time in the 80's because I was using this as my main source of income during the winter season. Summers were a struggle, however I purchased my home in Vail in the 80's when things were rockbottom, and my roommates/tenants basically paid my mortgage for me. I left the area and the business around 1990 for "greener pastures". Leaving, however, taught me one thing a couple of years later; I love the lifestyle, love the mountains, love the sport, and I missed them terribly.
Out of the blue, we ended up back in Vail, this time with husband and kids in tow (a little different from my swingin' singles days in the 80's). Now, having some of my own money and a partner who brings in the lion's share of the income, I am able to teach when I want, but we do depend on the income as well, since I am on a year long leave from my primary job as a stew.
The income will never turn you into a millionaire, but the costs are low to be in the business (other than equipment). You can, theoretically, live here with no car, there are no clothing expenses, and lunches are often bought for you, unlike the corporate world, where expenses are much steeper. No doubt, rent/mortgage are the major expenses, and, of course, finding supplementary income during the summer months.
Still, I wouldn't trade it for the world.