That sounds strange. Are you sure you didn't reserve a prepaid rental by accident? For most rentals, they don't even ask for your credit card. Maybe you reserved with your Budge FastBreak number and they had your card on file?
If this was not a prepaid rental, then what you experienced is NOT normal. Something sounds off here though. If you want to PM us your Budget conf# and last name, we'd be happy to help investigate. We help customers with over 100K rentals a year, so we've got quite a bit of experience in this.