Disappointed client

I am very disappointed to say, I have been a client with FNB for many years and I currently have a car financed with Wesbank, I am in the process of buying a new car and was informed by the dealer that Wesbank wants to give me a 16% interest rate.......where as another bank offered me 13.25% a bank that I have never before dealt with??? I am a "FNB Private client" and all that seems to stand for is the fact that I am paying a lot for an account every month?