Other than the title why even bother purchasing the movie rights?
Okay, firstly, I read the book quite some time before I, finally, got around to seeing the movie, so please forgive me if I'm not quite recalling things accurately.
With that out the way, there didn't appear to be any part from the book to feature in the actual movie, at least that I could remember. So, if that is indeed the case, why even bother to buy the movie rights in the first place just for a title?
Any fans of the book are almost certain to be fans of the overall genre anyway, and thus would be quite likely to want to see a big budget zombie movie, regardless of the title. So, really, there's no point in purchasing the rights just for that, as cool a title as it is, and I'm sure they could have come up with something just as enticing to those who aren't pre-existing zombie fans. It's not like the title is something special that could attract more significantly more viewers than something entirely original.
It just makes no sense to me.