They just go in and use it as they would any other card.
There should be a number associated with the giftcard.
Coffee snacks breakfast or lunch. Also if they are a regular Starbucks customer they can add it to their loyalty card and add to the value with specials
They would use it in a Starbucks store as they pay for the order
Take the gift card to a Starbucks. Anyone with the gift card can use it to pay for their purchase.
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