Prisoners in most states are literally underfed, and then "allowed" to buy more food, like a single packet of ramen for a whole dollar.

This is because many states are full of people who are both weirdly "Free market" brain, to the point that they believe it's a good idea to tell the warden "Any dollar from this budget that you do not spend feeding inmates, you get to personally keep" is a good idea because they have no knowledge of systems design or perverse incentives, and more importantly, because they genuinely want prisoners to suffer. No, this is not a joke. In some states, the budget for feeding inmates is explicitly a compensation package for the warden.

When people joke about "I should go to jail, at least I will get three square meals a day", that's just false. Most prisons are only required to serve two meals a day. The quality of those meals varies from "Okay for a middle school lunch if you put a gun to my head" to "Fyre festival had better food, and this is not a joke"