The film industry will always appeal to a broader range than novels. For a start many find a novel hard work, especially those with learning difficulties.

Imagine if you were dyslexic, you would struggle to read a book of that size, and especially the later mammoth books. However a film can be enjoyed in two hours, is cheaper (£5 for film, £9 for paperback, £16 for hardback) and is accessible to those not able to read the books.

Also the film can be watched by persons whose first language is NOT English, but they understand enough to converse in English. Therefore they could understand and follow the film, but not the book

Hope that helped dude