Old European fairy-tales do mention famine and war as a backdrop. Our ancestors were perfectly used to the condition of "mostly scarcity, sometimes abundance".

Old European fairy-tales do mention famine and war as a backdrop. Our ancestors were perfectly used to the condition of "mostly scarcity, sometimes abundance". You are correct that extreme scarcity will kill everyone, but places where extreme scarcity actually happens (e.g. Svalbard or Atacama) were never settled in the first place. Traditionally inhabited places (prior to the Industrial Revolution) were the ones that could sustain some population indefinitely, and if the situation slowly worsened, people abandoned them and went elsewhere, instead of passively waiting for death. And they took their memories with them.