I rode Kyushu last December. Convenience stores and grocery stores. Sushi bento boxes for next to nothing. Ate like a king every day.

Except on top of Mt. Unzen. No convenience store and the only ATM wasn't working. Climbed 1500m to get up there and only had enough cash for three eggs. Also it dropped below freezing. And some busybody Japanese Karen called the police on me when I was cooking my three eggs at 11pm, and so I had to move my tent. Good times...