Horrible Service

I went to the KFC drive through The Grove Nelspruit. Bought steeetwise 5 and gave the cashier a R100 note, she gave me change which was short with 10 cents, when I told her that she didn't give me my 10 cents she said" oh sorry we dont have 10 cents" and I waited and told her that I'm not going anywhere without my full change, she then told me to pick a coin which was probably dropped by someone on the floor! I refused to pick up the coin, she then called her colleague who picked up the dirty coin and handed it to me which I took. The coin was scratched and it have to print on the front that shows the value of it, I felt very insulted that as a customer to be given a picked up coin when I demanded what was mine. Firstly KFC decided to price their items that requires 10 cents and make it our problem? Can you imagine that if 2000 customers that buys from KFC daily are not given their 10 cents, in 1 year KFC *****s R67200 from customers? Why is it my problem as a customer that they don't have 10 cents amd when I ask for my change I get insulted? Like really?