It's nice because if you use your gift card from the app, it automatically converts the currency and the exchange rate is quite good. We've used ours in Mexico and Canada.
I haven't tried to use an actual reward for a freebee in another country, but using the card has been no problem. Keep in mind sometimes airport locations won't let you redeem rewards for free drinks, even though they usually let you pay with your starbucks card in the app.
I wasn't sure if using the physical card would be any different from using the app. The app has a barcode to scan, but physical only has a strip to swipe.
I don't see why they wouldn't be able to swipe it. But if I would recommend loading your card into the app so you can get the benefits of the rewards program.
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