The baseline for human nobles can be shockingly low; he had seen it firsthand.
A merchant who merely surpasses his peers economically can treat his impoverished kin like livestock, and nobles, who possess extraordinary power and are inherently superior to ordinary humans, regard the lower-class populace as expendable.
It's not simply about using them until they die; nobles completely disregard any objective reality. Whether it's natural disasters or wars, taxes are still collected. During a bountiful year? Even better, they double down in every sense on being inhuman.
A significant portion of the human nobility sees the lower-class as wild creatures, like Kobolds or Goblins. Even if most of them die, as long as some survive, they multiply rapidly and spread everywhere, requiring no consideration.