I never said that that Warcraft is strictly european.
But the influence of the basic setting (Which is Warcraft 1 and 2) is pretty much Tolkien, who drew part of his inspiration from Norse mythology.
The general setting (used to be) basically a high fantasy medival world with regular human kingdoms, Dragons, Dwarves, elves and so forth.
Obviously when the world expanded a lot of other races and cultures were added but the amount of that comes from european mythology still outweighs the rest.
My point i was trying to make was originally, people from western society are more open towards mythical creatures from Norse and Greek mythology, because it is very likely they already saw them in a certain shape or form in different medias, stuff that draws on japanese mythology probably less.