We're also again trying to hold human morality to giantess who large numbers of don't even hesitate to eat humans, and even some of the "nice" ones effectively go "oops, oh well" if they step on a human. The only reason some of the characters get upset about crushing the MC is because he's a human that has value to them at that point in their plots. Very few of them would be overtly bothered by crushing a random.
Even the humans of this world have a different morality than we generally do, let alone the demons, beastfolk and elves who also play a role in the world, which I get the impression that beastfolk and elves have far more sway in their respective kingdoms that are going to war than humans do.