Dry beans and fresh food like you described cost a large amount of time to prepare compared to processed food, and time is a luxury poor people do not have.
If you take a bus to work, you probably don’t have time cook.
If you take a bus to work, you probably don’t have time cook.
I know a lot of poor people and I assure you that many of them have plenty of time. There are certainly many hard-working poor who desperately need time back in their day and would cook if they had the time, but time alone would certainly not solve the phenomena of poor people not cooking. What many other poor people do not have is executive functioning skills, the ability to plan ahead, or impulse control, and some of them also have addictions or expensive recreational drug habits, or live in unsafe scenarios where cooking would be an absurd afterthought.
Furthermore, many of the poorest people are recent immigrants (Mexican, Indian, Middle Eastern, African) and those households often rely on home cooking even more than many affluent households do.
Ultimately, I think it's likely that stress impacts everyone's executive functioning, not just poor people, but poor people may have a higher stress burden and also probably had lower raw "executive functioning" ability to begin with. In Western countries, where the economies are primarily based on rewarding jobs that prioritize extreme logical abstractions, there is a clear casual relationship between measured intelligence* and lifetime earning potential. I believe that this (unsavory) point is too often left out when proposing solutions to poverty because it implies the existence of an inherent, unfixable difference in human ability. To me this difference is obvious and should simply be planned for, but to many others it's a myth.
I do feel passionately about this subject because one of my family members is developmentally disabled enough that she cannot live a normal life but not enough that she's obviously impaired, and the rate at which her decisions lead her to live the life of a pretty run-of-the-mill American poor person is astonishing. If we didn't pay for everything she needed she would fit in perfectly with the behavior and lifestyles of the people in the slum areas of my city, and in fact she's already done some stints there due to some friends she made when she was unwilling to live at the family home.
(* = I am not saying "poor people are poor because they're dumb" or "if you're smarter you'll make more money" or that "IQ is real", only that "when you select a random adult, the less well they're able to perform on western-style intelligence tests the less likely it is they'll have a lot of money".)
It's not that complicated. Long term thinking requires certainty. Poor people generally dont have enough economic certainty to plan for longer periods into the future and that's the cause of their constant stress.
This stress and uncertainty poor people experience can constantly create survival scenarios where a longer chain of consecutive decisions have to be correct than for an equally intelligent rich person.
It's not hard to do simple, health, quick meal prep. Hell, buy some veggies, wash them and eat them is health as hell. Make rice or beans in 20 min.
If you have enough time to walk or drive to get fast food, you have enough time to make a healthy meal.