Why... :(

Why... :( so I was at Starbucks yesterday, and to avoid embarrassing myself, i just grab a bag of popcorn. i pay for it, and they usually don't give receipts so i try to ask for a receipt, but it comes out as "c-c-c-c-c-c-can I--" the lady just looked at me irritated and said "you want a receipt?" ^("yes.") she gives me my receipt and turns around rolling her eyes.