I'm originally from Israel where eating sunflower seeds - garinim is a national pastime. People would carry bags of them into the movie theater and the sound of shells crunching accompanied the film like a soundtrack. And being Israelis, they would spit out the shells, taking aim at the seat in front of them. If you had the misfortune of sitting in front of someone with poor aim, you would have to shake the shells out of your hair after the movie ended.