You must have heard this one before in many variations.Here goes
There were two tramps walking down a Street talking about how hungry they were.
So one tramp says to the other watch and learn from a proffessional how I can get some food.
The tramp picks up old dog poo from the road and puts it on someones doorstep,then knocks on the door.
When someone comes out he asks them if he can take the dog poo 'cos he hasn't eaten for a couple of days.
The lady who opens the door feels really sorry for him and takes him inside and feeds him well,then gives him some money for later.
The other Tramp thinks my god that was easy its my turn now watch what I do,So he picks up a dry piece of dog poo and puts it on someones doorstep.
He knocks on the door and waits,a man opens the door and the tramp with his saddened face asks politely if he can have the dog poo on the mans doorstep.
The man says to him dont be stupid how can you eat that horrible old thing,and invites him in.
before entering the house the tramp looks back at his friend hiding in the bushes and winks at him with his thumb up.
The man takes the Tramp through the house and past the kitchen at that point the Tramp got slightly confused,
The man opened his back garden door and led the tramp to his Dog kennel,there lyed a massive heap of fresh dog poo,the man asks the tramp to help himself 'cos its all fresh.
the tramp looked at the guy and ran back the way he came faster then a bullet.