Her card was never charged. She has like 3-4 gold visas and none of them matched her purchase and the Wal-mart manager reimbursed a gift card to her instead so basically she just got a gift card for free. How exactly this occurred is beyond me. (I wasn't with her at the time.)
Someone before your mom must've forgotten to put their credit card back into their wallet after using it and left it on the counter by mistake and your mom might be just right beside the card when it was her turn to pay for the items and the cashier just picked up that credit card thinking it was your mom's when it was time for your mom to pay. Not everybody gives their credit card directly to the cashier when it's time to pay. Sometimes they really just put the card on the counter and expect the cashier to pick it up and swipe it for them.
If they check the security footage, they might be able to figure it out cuz this is fraud committed by Walmart, using someone else's card without their authorization.

