> Many students already do this. It's not uncommon for students to not buy a single textbook in a semester.

I never bought a textbook unless I absolutely completely needed it. Otherwise I did anything possible to get it if I needed it before outright buying the book. In some cases just using Google was enough for the class. Especially for most of my programming courses. Textbooks are so expensive, and half of the time you don't even go through the whole of the book, not even getting your money's worth because the semester is not long enough for said book. Math textbooks were my only exception, though the school did allow me to borrow them for a few hours.