A duck waddles into a bar, perches on a stool, and asks the bartender, "Got any grapes?" The bartender says, "No, we haven't got any grapes! This is a bar; we sell drinks! You can either order a drink or get out." So the duck leaves.
The next day, the duck waddles back into the bar, perches on a stool, and asks the bartender, "Got any grapes?"
"Look, it's just like I told you yesterday: we sell drinks, not grapes! If you're not going to order a drink, get out of here!" So the duck leaves again.
The next day, the duck waddles back into the bar, perches on a stool, and asks the bartender, "Got any grapes?"
The bartender yells at him, "For the last fucking time, no, we haven't got any fucking grapes! And if you come in here and ask me that question one more time, I'll nail your fucking beak to the counter! Now get the hell out of my bar!" So the duck leaves again.
The next day, the duck waddles back into the bar, perches on a stool, and asks the bartender, "Got any nails?" The bartender, momentarily nonplussed, says, "Nails? No, we haven't got any nails." "Good," says the duck. "Got any grapes?"