Regional KitKats would be a lot more impressive to me if they were actually confined to the region they supposed spawn from within. As it is, no one is exactly zealously guarding carrying them over the borders of one prefecture into another. In fact, no one seems to be stopping them from being sold at every major station in Tokyo and in particular at Narita airport. That's okay. I think the whole regional food thing is overplayed in Japan anyway and if you want to get on your yubari melon KitKat (a Hokkaido version), all you have to do is good enough at a claw game ("UFO Catcher") to knock the box into the hole. Trust me when I say it is easier said than done.