What we need, instead of denying this happens, is to find out WHY it happens.
We know why it happens. People like the sense of familiar. If you go to Spain you will find areas where a lot of British people live.
A lot is about family, social life and food.
Authodox Jews have to live within walking distance of a syngogue as they have to walk their on a Friday. It then makes sense for Kosher shops and cafes to be in the same area.
When immigrants move to a new country there are things they want, food is one. It is much easier to go to a shop where you can buy familiar food in a familiar language.
The test there would be who do they support during a sporting even? Holding a passport doesn't make you view yourself a British.
Have you ever asked a Scot who they want to win the world cup? The answer is usually, "anyone except England".
My Hong Kong born, brought up in manchester housemate of many years ago was watching a China vs England mach, he swapped his support at half time.
And have you ever watched the commonwealth games? The comentary is something like this.
John A is representing Scotland, he got a gold medal for England in the last games. His twin brother Fred A took a silver for Australia in the same games but is now representing New Zealand.
OK I exagerate, but only slightly.