1. Browsing a book store or library is a better experience than browsing any online equivalent.
2. It's easy in a print book to flip to the index or some other page, and back to the page, you were reading. In digital books, you leave your spot at your peril. It's very easy to get lost.
3. When you do lose your place in a print book, it's far easier to find it again than it is in a digital book.
4. #3 is partly because of the tactile sensation of the book in your hand, which gives you a lot more feedback than you think. The thickness of the pages you've read vs. the thickness of the pages yet to read; the position of the words on the page (left or right, top or bottom). Your mind makes a record of your location that's based on more than just what you're seeing.
5. Studies have shown that people retain more of what they read in print. This is probably because of this multi-sensory experience explained in #4, including even the texture and smell of the paper. Memories are closely associated with other senses.
6. If you want to review a book or blog about it, it's so much easier to highlight things, attach a sticky note, scribble in the margins, etc., and it's very easy to find those notes later. The disadvantage, of course, is that you then have to type them.
7. Print is easier on the eyes than backlit displays. eInk displays are a big improvement, but I fear they might go away. The trend seems to be towards the backlit screens. (What we really need is a device with both backlit and eInk screens.)
8. You can get used print books, and they're cheap. The "first sale doctrine" does not apply to a digital book, so you can't buy a "used" digital copy. (What would that mean, anyway?)
The printed version - even a hardback - is often much cheaper than the eBook version. This is a big part of the reason students buy hardbacks. Also, they can sometimes profit from the notes made by previous students.
9. It's much easier to quickly find what you want in a print book - especially something like a dictionary.
10. You don't have to wait for a print book to boot up, and you don't have to charge it.
11. It's easier to lend (or borrow) a print book.
12. There's also a vanity / signaling advantage to a printed book. Visitors to your home can glance through your shelves and see what kind of a person you are by the books you keep.