Duck under the bar

duck walks into a bar and plops himself on to a stool. The bartender, looking perplexed, asks the duck, “ What can I get you?” The duck looks at him for a minute and says “You got any gwapes?” The bartender looks at him and says, “This is a bar. We serve booze here, we don't have any 'gwapes’.” The duck says “Ok, thanks.” And leaves. Next day, same duck, same bar, same bartender. The duck jumps up and says, “Got any gwapes?” The bartender, getting annoyed, says, “I told you yesterday, this is a bar, we don't serve 'gwapes’.” Again, the duck says thanks and leaves. Next day, same thing happens. Except this time the bartender says, “No 'gwapes’. If you come in here asking for 'gwapes’ again I'll nail your feet to this bar!” Wouldn't you know it, next day, same bar, same duck, same bartender. The duck jumps up and the bartender says “ Let me guess, do I have any gwapes?” The duck looks at him and asks “ No, you got any nails?” The bartender, clearly confused, says, “No, why?” The duck looks him dead in the eye and asks, “So, you got any gwapes?”