For the foreign language boards, we give the local moderators some latitude for their section. If they want to allow English posts then that's fine with me. If you don't like it you should take it up with the local moderator there, or start a thread there and open a dialogue about it.
That doesn't change anything about the english sections though, posts here do need to be english.
Yes, in the Korean subsection, though it isn't that popular, the guidelines are spelled out in both Korean and English. If the topic or comment is related to Korea, Koreans/Korean speakers, English posts are allowed. No discrimination here.