No drumsticks at KFC

I ordered a steet wise two with two drumsticks at our KFC, when I paid the cashier didn't say anything of out of stock for drumsticks. When I parked to collect the order I was informed that they don't have any drumsticks. Its a Teusday evening, how don't they have stock? It's thinks it's unexceptable. How do you run a 24h franchise without stock.