Well yes, I feel your pain, but for reluctant readers (children AND adults!) who are interested in the film, anything to get them reading is good, and may in some cases lead on to them trying The Hobbit proper. Etc. etc.

This is one of my defences of the Harry Potter books - The Adult gobbled them up (and fast!) when he wasn't really reading for pleasure much at all.

The art books are often interesting. If you like reading books about art.