A man is walking his dog in a park when he meets another man, also walking his dog. They say hello and start to talk about their dogs. One has a chihuahua and the other a doberman.
They decide to rest for coffee and they walk into a local cafe. Upon seeing a ‘no animals allowed’ sign, the man with the doberman says "Don’t worry, put on these dark glasses. We’ll pretend these are our guide dogs".
So the men do this and go into the cafe. When the waiter comes over, he says to the man with the doberman "I’m sorry sir, but we do not allow animals in here. You’ll have to take that dog outside."
"But this is my guide dog," says the man.
"A doberman! A doberman isn’t a guide dog," says the waiter.
"Actually, a doberman is particularly suited to being a guide dog nowadays. They provide lots of security and they are very well mannered."
"Oh, alright then," says the waiter, and then he notices the other dog. "Excuse me sir, but you can’t have that dog in here," he says to the other man.
"Oh yes I can, this is my guide dog" says the man.
"But that dog is a chihuahua! A chihuahua isn’t a guide dog!" says the waiter.
The man exclaims "what, they gave me a chihuahua?!"