The Blind Cashier

A woman goes into Cabela's to buy a rod and reel for her grandson's birthday. She doesn't know which one to get, so she just grabs one and goes over to the counter.
The clerk was standing behind the counter wearing dark glasses. She says to him, "Excuse me, sir. Can you tell me anything about this Rod and reel?" He says, "Ma'am, I'm completely blind; but if you'll drop it on the counter, I can tell you everything from the sound it makes."
She doesn't believe him but drops it on the counter anyway...... He says, "That's a six-foot Shakespeare graphite rod with a Zebco 404 reel and 10-LB. test line. It's a good all-around combination, and it's on sale this week for only $20.00."
She says, "It's amazing that you can tell all that just by the sound of it dropping on the counter. I'll take it!"
As she opens her purse, her credit card drops on the floor. "Oh, that sounds like a Master Card," he says.She bends down to pick it up and accidentally farts.
At first she is really embarrassed, but then realizes......there is no way the blind clerk could tell it was her who tooted. Being blind, he wouldn't know that she was the only person around?
The man rings up the sale and says, "That'll be $34.50 please." The woman is totally confused by this and asks, "Didn't you tell me the rod and reel were on sale for $20.00? How did you get $34.50?"
He replies, "Yes, ma'am. The rod and reel is $20.00, but the Duck Call is $11.00, and the Catfish Bait is $3.50." She paid it and left without saying a word.