Risk means opportunity. With hard work, a little imagination and some luck a software engineer could end up a billionaire. The best a teacher has to look forward to is a penny pinching retirement.
You don't know about school teachers in Alaska obviously
Pop quiz - how many of that exact case do you know? Vs how many do you know who have been downsized?
Your example is correct - there is a value to that upside potential. But it is uncommon in the extreme. Fill in your own math and do your own calculation - what is 80K with no chance of losing job, vs X with 50% chance of losing job and 0.00001% chance of becoming a millionaire. (I hope you didn't really mean billionaire).
Keep in mind also - in general - these are not people of equivalent mental capital. Ever hear of someone failing out of teaching school, deciding to take an easier major like Computer Science? Many of the so called "dot com millionaire" types are of the type/capacity who chose engineering over med school.
Your "little luck" model also fails when accounting for huge free time of teachers. All summer multiple years to start my own business? Huge impact on potential to hit the big $$$$.
The monopoly provides no value to the consumers of education and captures plenty of value for the members of the monopoly.
Diva's Husband