If you just cut everything from "Later" in the third-to-last paragraph onward, smart readers would probably still get it but it would be less obvious.
I always find myself confused about the intentions of the joke or the joke teller when they end it in the way you propose. I'd get it, but then be wondering "did the joke teller get it?" or "was there some other punch line that the joke teller intended me to figure out but I didn't?".
It's similar to most of the tests I took in school. I'd spend most of the time figuring out what the teacher intended the answer to be rather than actually learning anything new.
You only have two votes right now, but they counted for -10, so probably 2 strong downvotes. You can see the number of votes by hovering your mouse over the number.
"The dumbest kid in the world"
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 dollar bill in one hand and two quarters in the other, then calls the boy over and asks, “Which do you want, son?”
The boy takes the quarters 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 the quarters instead of the dollar bill?”
The boy licked his cone and replied, “Because the day I take the dollar, the game is over!”