For instance, and only personally speaking, at the current salary level of teachers, I couldn't be bothered to take all of the crap that teachers take. However, were the salary to be six figures a year, with all of the same time off and benefits.....well, every man has his price. Whatever is subsidized, you get more of.
My personal experience with people studying to be teachers in college mirrors yours. I'd estimate 20% of them were there because they wanted to be (and honestly, I think that they'd be successful no matter what profession they chose, IMHO). The rest were people that washed out of their 1st choice majors.
The School of Education, and, interestingly enough, the School of Business, collected the washouts at my college. That says something but I'm not sure exactly what.
Come to most school districts on the East Coast metropolitan areas. A 20 year teacher with a masters in education makes upwards of $97K per year, plus benefits. We have 14 teachers in my district alone who make over $107K not including benefits.
Kids in my school district cost taxpayers $16K per year.
Believe me, teachers are not overworked or underpaid anywhere around here.