I know this may shock you, but some people can actually read more than one language. So even if they primarily speak English, they may also enjoy media in Spanish, Chinese, Japanese, or French. Also, it has been found that many people who speak these additional languages live in the United States.If I'm an English speaking user using the North American store, why do I constantly have to see apps in Asian languages? It's one of the many many annoying traits of Apple's vaunted App Store.
Sociologists are still trying to determine what would cause this large diversity of people to seemingly melt together within a certain geographic area, but they are certain the answer lies in a middle school civics or history textbook.