Well, it's both for racist and euphonic reasons. Many whites in Europe believe other Europeans aren't white. Nordics versus mediterranean types, etc. I still remember the shock of being called a WASP by a Palestinian friend of mine in college. I told him that I guess I was white (though I think of myself as being more pink than white), but I was neither Anglo-Saxon nor protestant. He laughed and said, you know what I mean. I asked him if all Israelis thought this way. We started speaking again after a week or so. Then decades later I listened in astonishment as a European friend (who was a Polish Jew who'd grown up in Austria after the war) explained to me how Turks were not European and Turkey shouldn't be let in the EU. Sigh.