re: Japan - I am not sure if your average Japanese family even eats that much fish...
lots of packets is not surprising - although, looking at the photo, it looks like packets of buckwheat noodles, breadcrumbs, tofu, packets of miso soup, fish/seaweed/sesame mix for rice etc., so not exactly unhealthy.
The mum in the photo is holding a big bag of rice which is the staple food.
Veggies in season and local are not particular expensive in Japan, but fruit can be (compared to the UK)
Imported bananas are cheap-ish (100yen/60p for a bunch), pineapples are about £1.50 each, local oranges are about £1.30 for six, local strawberries about £2.50 a punnet
the famously expensive melons etc. (£100 -200 or more, each!) are not really for ordinary people - they are bought by companies as gifts for other companies etc. Or by the mega-rich.