Fred and Esther and $50

Frank and his wife Esther went to the state fair every year, and every year Frank would say, 'Esther, I'd like to ride in that helicopter.'
Esther always replied, 'I know Frank, but that helicopter ride is fifty dollars, and fifty dollars is fifty dollars.'
One year Esther and Frank went to the fair, and Frank said, 'Esther, I'm 85 years old. If I don't ride that helicopter, I might never get another chance.'
To this, Esther replied, 'Frank that helicopter ride is fifty dollars, and fifty dollars is fifty dollars.'
The pilot overheard the couple and said, 'Folks I'll make you a deal. I'll take the both of you for a ride. If you can stay quiet for the entire ride and not say a word, I won't charge you! But if you say one word, it's fifty dollars.'
Frank and Esther agreed and up they went. The pilot did all kinds of fancy maneuvers, but not a word was heard. He did his daredevil tricks over and over again, but still not a word.
When they landed, the pilot turned to Frank and said, 'By golly, I did everything I could to get you to yell out, but you didn't. I'm impressed!'
Frank replied, 'Well, to tell you the truth, I almost said something when Esther fell out, but you know, fifty dollars is fifty dollars!'