First, some economic realities of academic publishing. University presses tend to lose money or do a little better than break even. They are not money-printing operations. There are probably some exceptions to this generality. Most academics do not make money writing and publishing — it is not worth their time if the only motivation was the money. Academics make money in publishing when they write a very successful textbook.
Second, some personal disclosures. I work in two areas of academic publishing. I write academic books and work in a bookshop that specializes in academic theology books. I am also linked to academic publishing in a third way as I teach, and so assign academic books as textbooks.
The fact that I produce books and receive royalties from their sales (piddling as these royalties may be) probably partially accounts for my strong stance against downloading copyrighted material. I did take a stance agains this before I produced books, realizing that photocopying books (which happened when I was an undergrad back when dinosaurs roamed the earth) or downloading scanned books is illegal. I don’t make copies outside of fair use for my students, didn’t before I was published, don’t now that I am published. I am pretty scrupulous about this. I realize that not everyone is so scrupulous.
Working in retail has given me a different perspective on academic publishing. In the bookshop where I work we give everyone the best price we can. We always discount 20% off the retail price where this is possible. Unfortunately, it is commonly not possible on textbooks because university presses give a short discount to retailers on textbooks. This is irritating to us in the store, and also to students. It seems backward, but see above. Textbooks are the one place university presses have a chance of making enough money to break even or do better. It is that whole captive audience thing. So part of me kind of understands it, though I find it irritating. In my mind, however, this doesn’t justify cranking out editions of very popular textbooks. That seems like pushing a good thing way too far.
So, as a producer and consumer of academic books what can I do? Well, do I want to publish with the Oxford University Press? Should I decline to publish with them because of their questionable ethical practices around the many editions issue, as exemplified in the Ehrman text? Do I avoid using Oxford University Press books as texts in my courses where that is possible? Yes, these are all things I should do. My own personal stance on this won’t change the OUP. But my conscience will feel better.