I vividly remember when I was younger, I would constantly press the "call flight attendant" button to request cookies on a 10 hour flight. She eventually just went back and handed me the box of cookies and I was pretty satisfied. When we disembarked, I realized how much of an jerk I was and gave her $10 I had in my pocket. Probably one of the sweetest and happiest flight attendants I've ever seen.
