You be the critic

There's this cool thing in the back of a book I checked out at the library. It says, "You be the critic" and tells people that have read the book to write a checkmark next to one of three categories that the book best fits into. The three columns are: Great, Good, and Don't Bother...
That's awesome! Why have I never seen this in a library book before? Do these things get put in library books often? Am I just inattentive?