My point is that there are structures to stories that the writer falls instinctively into. Right now I'm starting on a story and as I write the first scene I find that I'm thinking of "Mystic Pizza." As I go further into the love story, I'm thinking of "Braveheart" (don't worry, the girl isn't going to have her throat cut, but she does hide the relationship from her family and the discovery of it does prompt a war between sides). There is also a "Gattaca-ish" element to the story.
This may sound like a mishmash, but it is, in fact, a cohesive whole, and when you read it, you won't realize that the scene where the poor kids run into the rich kids loosely follows a similar situation in "Mystic Pizza". Movies act like visual guide posts, reminding us of the structures that already exist that we can mold into our own.
If you want to write, watch the movies.