Cash Finance Charges rip-off

I noticed a charge on my Standard bank Master card Credit card statement for Cash Finance Charge and queried it. The explanation given is that the charges is again Cash transactions and transfers to other accounts - this is understandable except that the client is not made aware of all charges and there conditions. So I transferred funds into my credit card to settle the balance, but I just rounded the amount and was left with a balance of R6.87. I was charged R222.41 on a balance of R6.87! I queried this and the answer given was that you will be charged until the cash balance is zero. What a rip-off! I'm changing to Capitec