Assume that there are two movies scheduled to come out on the same weekend this summer from two different movie studios. The movies are "Iron Man 9" and "The Hobbit 7". Advertising for these movies is very costly to movie studios, and since the movies are already established brands, people would still see them, even if neither studio advertised. Despite this fact, both movie studios end up spending large amounts on advertising. Using Game Theory, explain why this might happen.