The Economist suggests that Danish Hygge (or German Gemütlichkeit) might go hand in hand with exclusion of strangers.
Denmark’s own natives may rank it top for happiness, but the immigrants in the survey [among expatriates] ranked it 60th in terms of friendliness, 64th for being made to feel welcome, and 67th for the ease of finding friends. … If cultures are obsessed with the joys of relaxing with old friends, perhaps it is because they find it stressful to make new ones.