Brain Teaser
Buford and Festus went together to get a drink at the county fair.
Buford goes up to the counter and says, "A beer, please." 
The man working the booth asks, "Pabst Blue Ribbon or Schlitz?"
Buford asks, "What's the difference?" and is told that the Pabst costs 90 cents but that the Schlitz costs $1.
Being a connoisseur of cheap beer, Buford says, "Give me a Schlitz, please" and places a dollar on the counter.
Next, Festus says to the man, "A beer, please," placing a dollar on the counter. The man in the booth gives him a Schlitz.
How did the man in the booth know that Festus wanted the Schlitz instead of the Pabst?
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