The issue I'd have with that is mostly the quality of the book. I've paid 50 for a good book because it's sold as a premium book/limited edition, even for manga I've done that(the deluxe Berserk volumes are well worth the price, super high quality)...a spiral bound book is maybe worth 10 imho. This is just some fartsniffing professor making a quick buck.
50 bucks is nothing. I recently payed $270 dollars for a Anatomy and Physiology textbook.
My Federal Income Tax accounting class textbook was well north of $300 in 2020.
At least that's appropriate for the subject.
The issue I'd have with that is mostly the quality of the book. I've paid 50 for a good book because it's sold as a premium book/limited edition, even for manga I've done that(the deluxe Berserk volumes are well worth the price, super high quality)...a spiral bound book is maybe worth 10 imho. This is just some fartsniffing professor making a quick buck.