While electronic textbooks do let you skip randomly between pages, it would end up being a mixture of memorizing page numbers and looking at the table of contents.
Have you ever actually used a Kindle textbook? There's a bookmark feature that allows you to immediately jump to preselected pages in the book. It's infinitely more useful than having a bunch of stupid physical placeholders in a textbook that you need to jump around with. Also, I can search my textbook. Can you?