The university textbook market is pathological and unfair. At every turn the publishers , and the universities happily go along with it.
It taught me the value of a healthy secondhand market. For common classes like calculus and physics, the new price was about $80 or $100, but I could buy a used book directly from a student for $60, and sell the same copy directly to another student for $60 after the semester was over. But by the time I was taking senior‐level engineering courses, there were so few students taking them that used textbooks were hard to find.
To fight used sales, publishers would release new editions fairly often. Maybe there were justifiable reasons for a new edition, like fixing typos perhaps, but it was obvious to anyone who stuck with an older edition that the biggest changes between editions were the problem sets, in an obvious attempt from the publishers to force students onto the latest edition. Certainly it beggars belief that subjects like calculus and differential equations would see enough change in the field to justify the new editions as rapidly as they came out.
I often used international editions, which could be bought for $15 or so (when available). They were made with cheap paper and cheap bindings, but the content was identical. As usual, though, the publishers often changed the problem sets between countries. Since the rest of the book was identical, students with old editions or international editions could use the book normally just fine, only having to copying the assigned homework problems from a generous student with a current edition.
At my school, the University of New Mexico, couple of textbooks from mainstream publishers were published as “special UNM editions”; I would love to compare one of these to a mainstream edition to see if anything meaningful changed. I think it’s safe to assume that it was just another excuse to reduce the size of the used market and to change the problem sets around.
There were some cases where the professors wrote their own textbooks. It made sense a time or two in the more specialist subjects, but the moral hazard is obvious. The worst was when I took a Greek mythology class in the humanities department: the lecturer wrote the book, which was a consumable workbook, and wouldn’t accept homework on a separate paper, only written on a page from the book.
When I was in school, publishers were only just introducing the idea of supplemental online course materials, which of course expire at the end of the semester and can’t be resold. I shudder to think what the university textbook market is like now, when the used market can be so completely eliminated.
The publishers’ behavior is obscene, but what I find really reprehensible is that the university and the teachers went along with it, when they could structure their courses otherwise.
One of the few good experiences I had with assigned reading was a microprocessors class where the professor, who had a fair amount of industry experience, assigned only public datasheets and manuals. It makes such a difference when material is produced by a functional market, where the authors’ financial incentive is to provide thorough, functional documentation without grift. The contrast with university textbooks was so apparent.