In slovenian (tech) colleges, years ago most of the books were written by professors, and published directly by in-college publishers, so calculated to current prices, books cost 10-20eur (literally depending on thickness and size), and were resold and reused for many years. Even photocopied versions were available at a few photocopied places around, due to a size difference (A4 book shrinked down to two A4 pages, side by side on one landscape A4 page), and noone cared, not even the authors.

Checking the situation now, some are even available online, eg:

http://antena.fe.uni-lj.si/literatura/ed.pdf

Some are even unchanged from my times: https://www.fe.uni-lj.si/mma/Osnove_elektromagnetike_2016-02... (1999)

Basically, noone really cares.