Charged for a VALET!!

We received a car rental through our insurance. There was important disclosures that was discussed with us and we understood them . Never did they mention that we could be charged a valet fee. When I looked at the contract there was a section with additional fees which showed a valet fee but I didn't think anything of it because it was not even stated under the conditions when you return the vehicle . I am truly disappointed that we were charged R525 where we could have gotten it cleaned for R150... does Avis really think that we would have wanted to be charged that amount purposefully??? We made sure we looked after the car returned it with a full tank and obeyed the conditions we were told. I am not leaving it like this as the car was not even that filthy ! These companies make so much money and to charge that amount for a valet!!!