A few years ago I booked a weekly rental with Thrifty using the magic Card.
I brought all the paper work with me to the counter.
The agent told me I wasn't on the system, they had no cars available, the magic card and reservation/confirmation documents that I brought with me ment nothing to him, an additional driver is $10 per day, if I wanted to rent a car from Thrify it would cost 3 times more than the price of the confirmation papers and I would have to wait for a car to become available.
It was the ugliest experience I ever had at the airport.
The supervisor finnaly figured out what happened and gave us a car for the original confirm rate. They still wanted an extra $10 per day for an additional driver.
I'll never rent from Thrifty again. Ever.
Since then I joined National Emerald club for free. I automaticlly get an additional driver for free with decent cars and rates on the Emerald Isle.
Good luck all,
Joe