New Doritos burger without chicken patty

We could have reported this to the store itself, BUT when we recieved the burger it looked small, we asked the girl where we received it if it was in fact correct and she said yes. So, we believed her, after being disappointed spending the amount we did and receiving a burger as small as your standard KFC burger. As we got home (about 6km out of town) we opened up the wrapped burger. NO chicken patty was on the burger. We feel this UNFAIR and not right at all. Yes, KFC was busy tonight, BUT your 'checking' needs to be in place. If we drove ALL the way down to town and back again the fuek spend would be MORE than the burger itself! Why do we need to complain to het GOOD service?