More and more students are opting for cheaper textbooks (obviously), or for pirating or neglecting to purchase textbooks altogether, due to the expensive nature of these copyrighted and intellectually protected materials.
According to the Wall Street Journal (http://www.wsj.com/articles/a-tough-lesson-for-college-textbook-publishers-1409182139?alg=y), college textbook prices are jumping an average of 6% a year over the past decade - with no signs of relenting.
Personally, receipts for my textbooks per semester (on average, 4 or 5 books) have totaled hundreds of dollars. Not wanting to place so much financial burden upon my parents, I have in some classes to either search for PDFs uploaded to sites found from searches through Google, or simply not purchased the book at all, believing that I can learn everything through class and through online resources. And most of the time, I'm right - for most of my classes, I either haven't needed the textbook at all, or learned the concepts through some other form (namely, the internet).
Any knowledge inside of an expensive, multi-hundred-dollar textbook can be found online with a simple, easy Google search. Want to know something Finance related? Look it up on Investopedia.com. Want a quick Calculus refresher? Go to Khanacademy.org. The list seems endless. I passed Integral Calculus thanks to Khan Academy.
There are thousands of resources online that a professor can choose from in creating a curriculum or course schedule for his or her class. Why not pull from these materials instead of from textbooks that become easily outdated? Why not teach concepts in class then tie them to real world articles from the Wall Street Journal, or other news sources?
To me, when concepts are tied from class to real-world examples (rather than somewhat abstract examples from a textbook), they are much more easy to learn. I know that I appreciate it when a professor does this in one of my classes.