Your family member needs some satisfaction in a way that nothing you could buy her would provide.
Many purchase options offer some sort of reward, whether it be cashback, rebate, miles, store credits, etc.
Did this same family member (depending on age) used to tell the clerk "No, I don't want those Blue Chip Stamps today, as this purchase is for a gift"??? Or tell her bank "no, I don't want the 1% cashback on my ATM?
This is one of the most absurdo things I've heard in awhile.