I have rented through Costco Travel & Insurance and I have never been charged for second driver. Don't know if this holds for a 'cold/walk-in' rental.
I'm a member of AAA and they work with hert
Make sure you book through AAA and not another 3rd party site. Both drivers have to be AAA members for the fee to be waved. Again other 3rd party sites are already discounted rates and won't allow for an additional driver fee to be waved.
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