I think many Brits used to suffer the illusion that immigrants were, perforce, Anglophiles, who had, perhaps, spent their youth listening to the World Service, learning immaculate English and coming here out of sheer love for our way of life or because they despised their impoverished surroundings or small-minded compatriots.
Errr, nyoh. They're only here for the money* and, furthermore they have every right to behave just as the British Empire-wallahs did: - bring their culture and customs with them and flaunt it in the faces of the indigenous population.
At least they've had the decency to not conquer us, militarily, first.