[FrankenTan]

As I understand it, and in part how it is for myself; reading books can be a meditative practice.

Having a physical book can help someone focus and get in the mood, as well as help them create the enviroment around the book itself as they consume the contents.

An ipad or computer also has other purposes than reading, but a book does not.

Some people can do this with an ipad or a computer monitor, but I think the people who say there's no replacing a good book might prefer the in-part ritual around reading an actual book.

[edit] You might be right in that people will eventually create these things around their ipad, but I still think there might be a value in, even if not more valuable than having grep for a book, the single-purpose existence of books.