There's a minimum amount a human being needs to get by, and an amount sufficient to meet anyone's reasonable needs and wishes.
A just society would ensure that noone fell below the minimum. It would also ensure that nobody got more than a reasonable maximum. That's how it works in families, that's how it works in tribes.
When we hear of a family where one child is neglected and kept short of food and another gets overindulged, we'd know something was badly wrong with that family. If we came across some "primitive" tribe where the same thing happened, with some people starving and some people feasting, we'd know there was something badly wrong. If we saw it in a troop of chimpanzees, we'd know something was badly wrong...