Do people not realise there is a P+Pand Zombies book?

I've noticed alot of the hate on here regarding this film comes from the thought that this was just a random idea for a film from Hollywood who wanted to churn out another zombie movie.

It's not the case. Back in 2009 Seth Grahame-Smith wrote (or technically re-wrote) the story to include zombies in a playful yet respectful way.

I have no problem with people not enjoying the film (personally I thought it was ok but nothing special) I just find all the "Hollywood's-messing-with-a-classic" argument misinformed.