A duck walks into a bar...

...and asks the bartender, "Do you have any duck food?" The bartender replied, "No we don't because we don't allow ducks in here. Please leave.", so the duck left. The next day the duck came back and asked again, "Do you have any duck food?" annoyed, the bartender said, "I told you we don't have duck food yesterday, so don't come back." The duck came back day after day for a week. Finally, the bartender says, "Listen, duck. If you come back here again, I'll nail your feet to the bar." The very next day, the duck walks into the bar and said, "Do you have any nails?" The bartender looks around and says, "sorry we're all out." "Well," said the duck, "Do you have any duck food?"