Barber and the kid

A young boy enters a barber shop and the barber whispers to his customer, “This is the dumbest kid in the world.   Watch while I prove it to you.”
The barber puts a quarter in one hand and two nickels in the other, then calls the boy over and asks, “Which do you want, son?”
The boy takes the two nickels and leaves. “What did I tell you?” said the barber. “That kid never learns!”
Later, when the customer leaves, he sees the same young boy coming out of the ice cream store. “Hey, son! May I ask you a question?
Why did you take two nickels instead of quarter coin?”
The boy licked his cone and replied, “Because THE DAY I TAKE THE QUARTER, THE GAME IS OVER.”

Modified a little from Dead Dog