So then why did he just ask you to clear his cellar of giant chinchillas? Is he kidding?
This happens a lot in these games; the great hero is given trivial quests. These ruin his sense of being a great hero. Trivial tasks are okay at the beginning of the game, but quests should become increasingly bigger and more heroic as the game progresses. This is a great challenge, and is not always successfully met.
And why should the hero always do as he is asked? In many games, the only way to progress is to follow instructions; complete your quests to the letter, or you won't get a reward. And without that reward, you could never survive the next cellar, which features even larger chinchillas.