For me, this American Diner seems to represent a unity of individuals. By this i mean, even in the United Kingdom, a restaurant depicting these values manages to work. Anyone can eat there, regardless of their race, religion, wealth etc. It is also really interesting that the restaurant is called Captain America, of whom we all know is seen as the American hero promoting American collectiveness and unity.
Therefore, to me this image represented America because as well as depicting fast food for which America are most famous for, it also presents a collectiveness and therefore a unity of culture. This is something that I believe us britons associate so well with americans.