Japan provides plenty to eat and drink.
One of the big surprises was the many vending machines on busy street corners. They offer everything from coffee to beer to porn. Vandalism is rare in Japan.
You can also find the regular western brand names.

The basements of department stores are a convenient place to stock up -- restaurants can be extremely expensive.
I think that the kid was trying to beat the summer heat at his parents food stall.
Outside many Japanese restaurants there are plastic reproductions of the food inside. This is very convenient for tourists.
I ate a lot of convenience store takeout food.

One of the great sights of Japan is the Tsukiji Fish Market. It is the world's busiest and there is a vast variety to see, buy and taste.