[makeitdouble]

You could have bought a Suica or PASMO card (whichever, didn't matter), max it out, and not think about it for a week or so.

That's what I did with my parents a while ago, they even paid their small stuff at the convenience store with it. I'm not sure they even remembered how cash looked like during their trip.

To your point, yes, the railway system is clearly the futur, almost solely because of the Felica cosystem.