Failure to integrate is a huge issue, and it's currently tearing the UK and Sweden apart
I lived in expat-friendly suburb of Lisbon, Cascais, and commuted into Lisbon or airport as needed. Terrible rush hour traffic, though it was years ago.
Everybody wants to hate, but if you are a local and able to get in contact with these people there can be a huge benefit to you too.
I mean, that pretty much sums up everybody, but it seems to only be the upper classes who paint it as altruistic.