Depending upon how you look at it, it was pretty much the same when I was in university many years back. They did have recommended textbooks, but most of the instructors from the second year onward were doing exactly as you said.

There seemed to be an intense frustration with the textbook industry. This is as true for faculty members as it is for student. They understand how textbooks add to the cost of education, and are tired of the incredible number of editions that they have to deal with. (Even forcing students to use the latest edition requires instructors to adapt their courses to new editions.)

Textbooks don't fit into higher education environments very well either, since academic freedom is often valued more than a rigid curriculum.

I suppose that all of this, plus the limitations of ereaders, means that the right ereader for school is no ereader at all. Tablets are only slightly better, but computers or old fashioned hardcopies are the best way to access print. After all, this allows for information to be compiled from a variety of sources. Some of these sources are better in that they are developed with the practice and objectives of higher education in mind. Some of these sources are better because students are learning how to use primary sources rather than distillations.

As for primary and secondary education, well, that's somewhat different. Yet even though it's somewhat different I doubt that you'll find that dedicated ereaders (either devices or apps) are any better. First of all, I haven't seen any solid proof that it's cheaper. (Sure, you have claims. Yet the cost of educational resources often tear those claims to shreds.) Compatibility with school resources and licensing restrictions often make independent purchases impractical. Finally, there is a push to use more interactive materials at this level.

It would be wonderful if education could jump into this digital age, but it is being held back by the industry as a whole. I would not suggest leaping over the cliff built by industry.