Here is how the gift card scam works (in Australia)
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Yes they do still get activated at the checkout. But when you go to redeem, the code is missing the last digit or two so it doesn't work. People take the unactivated gift card, tamper with it to get inside carefully so it's not detectable, scratch and get the code, remove the last digit or two, replace the scratch off layer, put the unactivated gift card back on the shelf. Then after you activate the gift card at the checkout, they redeem it.
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