I lived in a Japanese university dormitory for a year. Alcohol is absurdly easy for under 20's to purchase. There is essentially no checking of IDs in shops.

I lived in a Japanese university dormitory for a year. Alcohol is absurdly easy for under 20's to purchase. There is essentially no checking of IDs in shops. Most shops have a touch screen point of sale system that will ask "Are you over 20?" if you buy an alcoholic product. Some of those systems only have the "Yes" answer button...