This isn't a surprise. There's a reason large cities have Chinatown, Little Italy, etc. Immigrants are more comfortable keeping their lives mostly within their own community that shares the same language and cultural elements. While I don't think it's all that healthy to avoid integrating with the society you move into, it's understandable to see people take the easy/comfortable route. Hell, I'd probably wind up doing the same.
I have a Greek acquaintance who lives in my city's unofficial Greek neighbourhood. Everything from groceries to bakeries and cafés, it's all Greek and he doesn't like to stray much from his routine in these shops. All the owners and patrons know each other personally. They get to feel like they're still back home. It keeps them sheltered a bit too much from the rest of us, but hey - they have a real community versus me that doesn't know the first name of anyone that serves me in any of the shops I frequent.
People move somewhere for a reason: most migrants (they are white so they are usually referred to as expats) in my neigborhood in south Spain are Brits who came for the weather and low prices: a lot of them simply want to live in a cheaper and sunnier UK. They do not want to integrate as that is not why they came. Same for the Germans; we have an entire town where everything is in German. Some come for the different lifestyle and Spanish culture; those integrate fast but it is a minority.
I have a Greek acquaintance who lives in my city's unofficial Greek neighbourhood. Everything from groceries to bakeries and cafés, it's all Greek and he doesn't like to stray much from his routine in these shops. All the owners and patrons know each other personally. They get to feel like they're still back home. It keeps them sheltered a bit too much from the rest of us, but hey - they have a real community versus me that doesn't know the first name of anyone that serves me in any of the shops I frequent.