Dollar Car Rental

Beware of the tolls in Dallas Texas. I inadvertently ended up on a toll between 7/2/2017-7/6/2017 twice which I immediately corrected. The tolls came to $3.21. After I received a notice from them 8/27/2017. I contacted them. Dollar Rental Car would not allow me to pay the Toll company directly but instead they have a Dollar Processing Service that handles "fines" out of AZ. This company charged me $30 ($15 service fee) for each toll. I am overwhelmed with how illegal this should be. I will never ever do business with Dollar and before I rent again I will make sure I read the "tinny tiny print." Confused Consumer...