Why are there blogs in print?

A while ago I asked "Why is there still print?". Asked, but didn't really answer. If books area test case for going digital (again leaving aside that text is fundamentally digital), then a blog, which is already available online for free, has got to be the acid test. Why on earth would one put a blog in print?

In Conversational Reading, a blog in form if not name, Levi Stahl examines the role of self-publishing (that is, print self-publishing) in putting blogs in print and tells why he has bought not one, but two self-published books adapted from blogs. Essentially, there's something about a book.

It's nice to have an index in the print edition, though.