Rice syrup + corn syrup are used in pretty much every savory dish, subway stations often have a bakery that sells sweet pastries (filled with bean paste), Starbucks style coffee drinks are also popular, people snack dried octopus (loaded with salt + sugar)...

I loved the food, but it was not at all what anyone would consider healthy.

(Instant Ramen are also extremely popular, industrially produced fried noodles with way too much saturated fats + sodium)

It's total calories, not just calories from sugar. And I already said that part of it was simple, remember? It's in the post you're replying to!

The question is why they have better balanced calorie intake. It's certainly not lack of sugar availability.