Step 1: Context of the story.
In the story 'Once Upon A Time', the young visitors mock the old man and his narration. Their behavior is disrespectful.
Step 2: Reason for reprimand.
They are reprimanded because their act of laughing at the old man shows a lack of respect and understanding towards elders.
Step 3: Conclusion.
Thus, the reprimand was a lesson in showing respect and sensitivity.