1. Yes.

2. Yes, publishing is a racket run by the textbook companies. There's a movement towards open source textbooks that I hope continues to grow for this reason. To BYU's credit, they are pushing faculty to find good open source textbooks for this reason. Unfortunately, there aren't as many quality open source ones yet, but there will be.

3. This is a funny paradox. Some just like teaching though and give up opportunities they had in private sector, but it is a funny irony that probably the best at what they do are doing it, not teaching it.

4. This one you got dead wrong because faculty make substantially less than peers with equal credentials who are in the private sector. The salaries are most certainly not extravagant. In my field, you can make about 50% more in the private sector. I just like teaching and university life, so being faculty works for me. But I certainly don't do it to get rich.

There are many other problems in inflated education costs worse than faculty salaries, and this has been documented in places like the Chronicle of Higher Education.