Why add a love interest?
I've both read the book and watched the film, and I thought the one big and unnecessary change they made in the film adaption was adding a love interest for Griffin. Granted, she played a very minor role, but still - Was it simply because a beautiful woman in the movie would make it more marketable? Or was it perhaps uncommon at the time to have a movie without some sort of love relationship?
It didn't bother me much, I just didn't quite see why this was done.