I think the person who wrote that letter is totally wrong. I am currently finishing up my student teaching assignment, and am very busy. I believe I know more than your letter writer about this whole subject. Every single minute of educational time that I attended as a CPA was paid for by the various establishments at which I worked. The comment about teachers making more money because of being required to take classes and earn degrees is thus invalid.
Teachers pay their own way.
Where I have spent the fall, most teachers are in the building at least from 7 a.m. to 3 p.m. This does not include the time spent at night and on weekends correcting papers, creating tests and future work, and writing lesson plans. Also, there are the countless hours spent after school working with the various student groups, taking students on field trips, etc. for which there is no hourly pay. When most business people travel, it is not by bus, and the accommodations are fairly comfortable. When students need to raise money for these trips, the luxury level goes down quite a bit.