Another thought....that may be the hourly wage, but teacher do not get paid in the summer and very few good paying jobs will hire someone for only 6 weeks. So, to a degree, you DO have to look at their yearly salary and not just the hourly.
The problem is, it is the professional 'education' cartel that mandated the credential. It's what keeps civic-minded chemists, businesspeople and many others from leaving the private sector to do teaching work (except in a few places where they might still teach in private systems.) As shown repeatedly by many, including Gatto and Martin L. Gross, the advanced "Education" edifice is nothing but a fraud upon the higher education system and the people who are forced to spend more money to often be indoctrinated. It's that segment of higher education that most often advances the detrimental fads like whole-word learning and the like.