Extremely bad customer service

I had a very bad experience today after many years of going to this garage and will never go back there ever. A very rude attendant screamed and shouted at me after he let the client that came after me take my place at the petrol pump as I was waiting to drive into position after the car infront of me moved. I was already waiting for more than 7 minutes as all the pumps were full. And instead of telling the client that just drove in and parked behind the car being attended to that I am infront of the car being attended and first inline and should be attended to next.