I'm going to have to chime in on the cash. Cash, cash, cash! Japan is a cash-based society. Some great examples? Not a single store in my whole town takes credit, not even the grocery stores! Or take Arashiyama's gift shops for example. Of all the omiyage places, I found only 1 store that took credit, out of at least 20 others. Not to mention Japanese bank/atm schedules are horrible.