This was not idle conversation. These people were in pain. They recited their story of Jesus as they had come to know him. They recounted the dreams they had started to dream. They rehearsed dreams that had seemed so real, so possible because of their life with Jesus.
Nothing hurts quite so much as shattered hopes.
Nothing is quite so painful as a beautiful dream of something long-desired that ends suddenly and is unfulfilled. Nothing is quite so bitter as the acrid taste of stark reality that a dying dream leaves behind. These people were suffering from just such a loss. In response to their distress, Jesus told them a story. In fact, he told them a great many stories.