A duck walks into a bar, "got any nuts?"
Barman says, "sorry mate, we don't sell nuts, just drinks". The duck leaves.
An hour later the duck returns, "got any nuts?"
Barman replies, "no mate, like i already told you we only sell drinks". The duck leaves.
Another hour passes, duck returns again, "got any nuts?"
Barman is getting angry now, "I keep telling you we haven't got any bloody nuts". Duck leaves.
Yet another hour later, in swans the duck. With the barman snarling at him, the duck asks, "got any nuts?". Barman completely loses his rag, "listen you stupid fucking duck, stop asking me if we've got any fucking nuts, we don't sell nuts, only drinks. Now order a drink, or get out. If you ask me one more time if I've got any nuts, I'll nail your fucking beak to the fucking floor.
Duck thinks for a moment, "got any nails?" Barman is confused, "no".
Duck replies, "got any nuts?".