Sorry yes, not all food is grown like I've suggested but a lot is.
My wife's family have a food business in Japan and they have better insight into this. The bulk of what they do is source high quality ingredients for restaurants and a fair amount of it is niche. The most memorable were edible flowers from a specific place in Japan, mushrooms from a different corner of the country, specific fish from certain markets, the best cuts of Wagyu beef.
They have a little corner shop too for the locals but in general the produce is many times more expensive than you would see in the West, however the food is delicious all year around not just when it's in season.
It was a real novelty when my mother in law came to visit and was able to buy strawberries for about £4, when in Japan she's used to paying something like £30+.