A man and a duck walk into a bar, the duck says to the bartender “Got any grapes?” The bartender says “No, I don’t have any grapes.” The duck and the man walk out, sorely disappointed.
So the next day, the pair walk back into the bar, and the duck asks the same question, and gets the same answer.
The day after, they walk back into the bar, and again, ask the bartender, “Do you have any grapes?” The bartender, having still not figured out why this duck seems to think he may have some grapes, says to the duck, “No, and if you come back in here tomorrow and ask me if I have any grapes, I will nail your bill to the bar!”
The duck turns to his companion and shakes his head, the pair walk out of the bar.
So the next day, the duck and the man walk back into the bar, and the duck asks the bartender “Got any nails?”
The bartender says “No.”
So the duck says “Got any grapes?”