There was also a second hand bookshop, where you could buy books for about 25% of the original price and usually sell them back to the bookshop for about 20% of the price at the end of the year, so they just got restocked most years and sold to the next batch of students needing it. This system only broke down when the course changed substantially, but in practice that was usually only about 1 of the 10+ modules each year.
In my 3 year course, I probably read about 100 relevant books cover to cover, bought maybe 3 full price because I knew I'd want to keep them for longer than the course, and kept 2 of the second hand books rather than selling them back.
Back then, I also had friends studying law, and they had to pay a fee at the start of each year, but would receive a pack each term that was several inches thick of photocopied case material. Presumably that was because they weren't predominantly reading to learn and internalise the material, but they needed to constantly quote specific sections at multiple points during their assignments, and so pretty much everybody needed the same material at the same time. But in that case, the university had permission to duplicate the necessary material.