What I've read of history shows it to have been full of wars with things like genocide and mass rape. We didn't even have a name for genocide until after WW 2 - it was just a standard thing that happened regularly.

And pillaging was just taken for granted as a standard solution to the problem of supplying an army in the field. It was much easier to take whatever the local peasants had and then move on than to have a good supply chain. The fact that the peasants often starved as a result was just one of the costs of war. Better them than us, and we have the weapons.