From what I've seen of families in poverty, it is usually less about them fitting into the current environment and more an issue of them having a surrounding culture that makes it hard to take advantage of the current environment.
A simple example is that people in a poverty culture tend to spend money immediately on short term gratification. On one hand, we could assume this is because they are foolish, but many have experience that if they try to save $20 for something longer term, someone in their household will end up just taking the money for something else. So their are acting rationally by trying to convert that $20 to something that will bring pleasure to them rather than deferring the pleasure only to lose the ability to spend the $20 on something they would enjoy.
Citations are of course needed, since I find the idea that most poor families have this pot of money anyone in the household can loot kind of bizarre. In the end, can you really blame a poor person for spending $3 on gatorade instead of water? That $2 price difference might amount to 0.1% of their monthly rent. You probably feel a lot happier at the end of the month eating a variety of things versus rice beans and water day in and out until you die, and the overall financial outcomes would probably be the exact same since no one is getting out of poverty through cutting out snacks and tasty things. They get out when their job changes and they are paid substantially more than the difference between buying a sandwich and making your own would be.
A simple example is that people in a poverty culture tend to spend money immediately on short term gratification. On one hand, we could assume this is because they are foolish, but many have experience that if they try to save $20 for something longer term, someone in their household will end up just taking the money for something else. So their are acting rationally by trying to convert that $20 to something that will bring pleasure to them rather than deferring the pleasure only to lose the ability to spend the $20 on something they would enjoy.