Hmm, I think after checking this topic for a while now, they've just sent this to everyone, in case it applies to you. They assume, as a foreigner, we send and receive money from abroad. They expect everyone to fill it in, so they can detect if someone is doing something illegal, but if you haven't filed it in and not doing anything illegally, it won't be a big deal as there's no money transferred across the borders. But later once you want to do this, you might run into some more paperwork, I guess.