Refund Processing Fee

I was charged an extra $40.00 refund processing fee that I did not agree to.  How can these places just take money from our accounts like this without our prior authorization?  I agreed to pay 93.59 for a service which should have been free for the convenience of their service, and then they went and charged me $40 more dollars on top of it.   When do the little guys get a break.  This is ridiculous.