Cash is still king in Japan, everyone uses cash. Any foreign worker can open a bank account in Japan, it's easy. So that excuse is bunk. There are a few new payment options around but every register, even self registers accept cash. In fact many stores, even one big drug store chain, only accept cash.

Cashless is coming be ready

I wouldn't worry about it in Japan. They've had mobile pay on their flip phones we had atms with dial out fees and cellphones still charged by the minute

They had color TV and really decent mobile games too, while we were stuck with snake and text news