I agree. Of course an e-book device is a lot handier to carry than several books, but at least if you leave a book behind on a bus, at a cafÃ©, etc. the most you're out of pocket of is the book or two left behind. If you leave an e-book behind, that could be your entire collection lost!
Another advantage with physical books: Sharing a physical book is as simple as handing it to a friend for a while. Sharing an e-book is not only more complicated (especially those crippled with DRM), but the publishers see you as a pirate.