Ok, unrelated dissimilar people can sometimes become in-group to each other. The fact is they don't more often than they do. People from different cultures rare

Ok, unrelated dissimilar people can sometimes become in-group to each other. The fact is they don't more often than they do. People from different cultures rarely find each other suited enough for friendship, naturally stay apart and normally only form this sort of bonds under external circumstances. Hell, even French-speaking and Dutch-speaking Belgians consider each other "other".