Courier Guy Over Charges

I was forced to use a courier this week because the company I purchased from wouldn't ship my item. The courier guy charged me R370 for a parcel under a Kilogram to go from Johannesburg to Kroonstad. In my eyes this is blatant overcharging and I expect better from such a large and supposedly successful company. When I contacted them they blew me off with a standard reply that this was the normal rate. They charged the for a 31kg parcel when my parcel probably only weighed 1kg if that much. What a *******.