A man goes to a bar with his dog. He goes up to the bar and asks for a drink. The bartender says 'You can't bring that dog in here!' The guy, without missing a beat, says 'This is my seeing-eye dog.' 'Oh man, ' the bartender says, 'I'm sorry, here, the first one's on me.' The man takes his drink and goes to a table near the door.
Another guy walks in the bar with a Chihuahua. The first guys sees him, stops him and says 'You can't bring that dog in here unless you tell him it's a seeing-eye dog.' The second man graciously thanks the first man and continues to the bar. He asks for a drink. The bartender says 'Hey, you can't bring that dog in here!'
The second man replies 'This is my seeing-eye dog.' The bartender says, 'No, I don't think so. They do not have Chiwauas as seeing-eye dogs.' The man pauses for a half-second and replies 'What?!?! They gave me a Chihuahua?!?'
