I graduated a decade ago but there was a pretty decent post-semester market for people selling their textbooks to other students (mostly via posting in various Facebook groups). Given the cost of college nowadays, if that ends up saving students a bit of money, it's probably worth it over saving the textbooks themselves.

Most years my parents ended up just driving my stuff to my aunt's house where she kept it in her garage over the summer after I packed it all up since I grew up several states away but my aunt loved in the area, and by the end of senior year, the textbooks I never managed to sell had added up to almost an entire extra bin (which was heavier than any of the others because they mostly just had clothes). For people who didn't have parents who loved driving everywhere in a large enough car or relatives in the area, this seems like it would be even more annoying (potentially ending up with just donating the leftover textbooks or maybe leaving them on the street like furniture and stuff often is at the end of the year on campuses). If people want to keep their textbooks, more power to them, but I'm not convinced that having a cheaper way that also simplifies the logistics of moving isn't better.

I'm a professor at a community college in Silicon Valley, and my students use online textbooks. I try to use Creative Commons or other libre textbooks, but sometimes I use paid textbooks when they are heads-and-shoulders better than their libre alternatives. Some e-textbooks can be accessed on a subscription basis. I admit I prefer non-subscription materials, but a colleague advised me that often the book that students learn from is different from a good reference book that students can use once they've already learned the material. For example, my colleagues and I have had great success with an online, interactive textbook for discrete math. While the subscription is unfortunately only valid for the duration of the course, once students have learned discrete math, they could buy a used copy of Rosen's discrete math textbook as a reference.

The nice thing about e-textbooks is not needing to carry around a bunch of heavy books. I remember the tomes I had in my college days, such as Stewart's Calculus.

I bought as few textbooks as I could, but the few that I did buy are sitting in my parents' basement bookshelves somewhere.

In college ATM and while I usually keep old textbooks, I have sold a couple on ebay to free up shelf space.