i agree, it's not a plothole, but they pretty much did say those books were mandatory reading for the movie, else they would not have come out a week before the movie release date! movies always have holes in the sense that they only have 2.5 hrs to tell a tale that takes 10 hours to read, so so much is left out of movies that only someone who doesnt care about story at all would just watch the movie and call it a day, anytime a movie/book combo is out i always read the book if i saw the movie first and liked it, books are always so so much better...
Well obviously, books are always better then the movie because of two things. Btw when have they said, that the books were mandatory?
1. Books are not limited by a budget, in what they can and cannot do.
2. More information can be given, because the book isn't on a time slot in which it has to be cut.