Hello Airmann,
I've found the same situation in my ME airline.
but, it wasn't any different back home honestly.
It is just over magnified here where you have people much more obviously belonging to nationality groups. It may be evident by the way they look, it is definitely obvious by the way they speak.
back home was the same, just more subtle.
honestly, I think that it has something to do with being humans.
They (!!!) are social animals. and they tend to form groups, and to create a sort of hierarchy within those groups.
pilots tend to be as human as others, and form groups of pilots.
being a troll, I tend to hang out with trolls most of the time, which leaves me very little time to get to know humans better...
but I'm digressing now.
essentially the answer is:
same same, but different
Regards,
KL