being poor is expensive

In systems thinking, this is an example of a self-reinforcing negative feedback loop. Some examples:

• The ownership cost of cheap good is higher in the long run. Higher-quality (and thus more expensive) goods last longer and are less espensive to own, if you can afford the up-front cost.
• Buying in bulk (e.g. groceries) saves money, but only if you have the cash flow to support it.
• With health, preventative care is an up-front expense many can’t afford, which would prevent the need for more expensive care own the line. Given that society often ends up footing the bill, this is a strong financial case (to say nothing of the moral one) for making healthcare a free, public good.
• Many banks have low-balance fees which keep small bank accounts from growing. Banking should be a free, public good.
• Credit card rewards points are a transfer of wealth from the poor