The point here is that the pizza goes neglected, often untouched, and before you know it the story is unfolding. This universally enjoyed Italian delight just doesn't get the kind of recognition within the movie industry that it has so rightfully earned among American households. Pizza is delicious, and it doesn't deserve to be used for a cheap laugh, or as some kind of tool for directors to establish "hangin' out" in their movie before they get going with the action. Who will stand up for the pizzas, who? All I'm really asking for here is recognition. Next time you're watching a movie and see this kind of neglect happening, point it out. Look around to your friends and family, and say "Hey, what about the pizza? Who will eat the pizza?"--for the pizza's sake.
Some examples of movies with neglected/abused pizzas: E.T., Home Alone, Spider Man 2, She's All That
Find your own neglected pizza, and show it some love.