In fact, they have, and in some cases, even more so. Take your food example, for instance. There are about 28,500 Italian restaurants in the US (not including Pizzerias). Yet there are about 41,000 Chinese restaurants and 54,000 Mexican restaurants in the country. There is one common thread, however. These restaurants almost universally serve "Americanized" versions of food that bears little resemblance to the actual food served in Italy, Mexico, or China - typically using locally available ingredients, seasoned to appeal to the broader American palate.

Although the U.S. views itself as a "melting pot" of cultures, it is not nearly as homogenous as we like to think. Immigrants (and their cultures) are not uniformly distributed across this vast land, especially during the mass immigrations of the late 1800s and early 1900s. While Italian culture features heavily in the northeast, German and Scandinavian culture is seen heavily in northeast, rust belt, great lakes region, and the prairies. East and South Asian cultures have noticably influenced the west coast, despite strong resistance, such as the Chinese Exclusion Act and the Internment of Japanese Americans in WWII. Latino culture is very visible in the American southwest and Florida as a remnant of when those areas belonged to Spain and Mexico. Similarly, French influences measure heavily in Louisiana, not just in food and social interactions, but also in its legal system.