Like assloads of beer.
Forget about fresh produce or fresh baked goods or fresh anything. Canned vegetables are as cheap as a gang tattoo, and every poor person I knew (including myself) had them as a staple of their diet. Fruit was the same way. Canned peaches could be split between three kids for half the cost of fresh ones, and at the end you had the extra surprise of pure, liquefied sugar to push you into full-blown hyperglycemia.
If it wasn't canned, it was frozen. TV dinners, pot pies, chicken nuggets ... meals that can be frozen forever, and preparation isn't more complicated than "Remove from box. Nuke. Eat." Because of that, by week two, half of everything we bought would be freezer burned. Just like with the canned food, you grow up thinking that this is the way it's supposed to taste. It's not that you grow to like it, necessarily, but you do grow to expect it.
Once You Escape ...
To this day, my kids won't eat fresh green beans. There's such a huge difference in texture and taste compared to the canned version that they're honestly like two different foods. None of us will eat homemade macaroni and cheese. If it doesn't come out of a box, it tastes weird. And the list is a mile long. We've eaten these things for so long, we've grown to prefer them to the fresh version.