"A man goes to a bar with his dog. He goes up..." joke

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?!?"