Seeing eye dog

This man goes to a bar with his dog. The guy goes up to the bar and asks for a drink. The bartenders says, "You can't bring that dog in here!" The guy doesn't miss a beat. "This is my seeing-eye dog." "Oh man," the bartenders 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 guy 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 bartenders says, "Hey,
you can't bring that dog in here!" The secondman replies, "This is my seeing-eye dog." The bartender says, "No, I don't think so. They do not have Chihuahuas as seeing-eye dogs." The man pauses for a half-second and replies, "WHAT?!? They gave me a Chihuahua?"