>>535269680
It's because JP server used to have dedicated patch streams before so there's no need for the code. And it's not like the garbage global gets, like actual actual streams with emcees and shit.
Now that they killed that too, people aren't actively looking up info about the game and that's them trying to somewhat solve it. Like you said, there's literally no need for codes even on global servers when they can just send it through mail to everyone.
It's all engagement bait, so people would ask, look, search or even talk about the game(codes) in the slightest way possible.