alt Hacker NewsWhen I was a grad student, I pointed this out to my poor neighbor with lots of health problems (5 pills a day!) who was shocked that I ate such expensive food despite being poorer still.
15 years later she's 50 lb lighter, takes no daily medication, and we have a mortgage and three kids. That's right, I fixed her up and married her.
It has been my experience, as a general rule (so it may not apply here), that people who grow up in the city are the worst at this.
People with strong rural roots, or who grew up in rural areas, tend to have lived in houses, have freezers, space for long term storage of items, and may have personal knowledge of canning, and food storage. If one grows up in an apartment, there may not be space for a shelf with canned food and bags of rice and potatoes.
I find that during harvest times, last year's canned foods are marked down. The logic being, I think, clear out their warehouses and get people to take last year's stuff home. And if you have space, you can take advantage of such things, and save, save, save.
For food, poor rural people often have better outcomes than city folk, due to the ability to store when sale items are found.
So when I read stories such as yours, I always wonder. City girl? Country boy? And as I said at the start, this is not a hard fact, just something I've noticed being a common reason why some people just "don't know".