25 cent shave

A man entered a barbershop and asked for a shave.
After the shave, the barber said, "That will be a quarter, please."
"But," said the man, "Your sign says two bucks for a shave. How
come only a quarter?"
The barber answered, "Once in a awhile we get a guy that is all
mouth and we only charge him twenty-five cents!"

That's actually a good one. That means that he has no facial hair right or am I missing out on something here?