Actually, their most effective gimmick is to include random handshake meeting tickets inside the albums, so if you want to have a higher chance of getting the tickets, you have to buy a lot of albums. Not long ago, there was a japanese fan who bought like 1000 copies of the single just to have higher chance of getting the handshake meeting tickets...really insane.
PS: I just looked at the weather forecast for Japan and suddenly realised why this single is not selling...tokyo's temperature range is 17-23 degree celsius, what WINTER? haha