Well, some of you always want a special PKMN on Wi-Fi. I think I have found the pattern to the events for the bit of you who don't see it.

Movie Events in Japan: They are given out wirelessly on Mystery Gift so that is why Toys 'R' Us & GameStop do it, they are the equal to the movies handing events out wirelessly.

Wi-Fi in Japan: If it is Wi-Fi and has been given out more then once, NoA will do the same for the Event for USA/European/Australian players.

Simple.