The Kojin of the Blue refer to themselves as the Kojin of the Blue, in spite of the fact that they are green. The humans in-game are confused by this, as well, but it would be rude to refer to them as Green when they desire to be referred to as Blue.
Since there is in-game dialog where this difficulty is explained to the player - dialog that exists in the Japanese, as well - trying to pave over it all just because someone might THINK a localization error is going on seems unwise. This is especially true if you consider the fact that in future updates, the Japanese dialog might refer to this Green/Blue confusion again. I think they did the right think in keeping it, and rather than trying to explain the archaic Japanese origins, play it off as a quirk of the Blue tribe that everyone just goes along with.
