>was already redeemed in some way
This is the important quote showing that the gift card was not legitimate.
What matters is that the purchaser had every reason to think that it was legitimate and they were not the malefactor in this scenario, but they still got banned.
do you think that makes it ok? they walked into a store, tried to pay money to apple and as a result they had their stuff locked forever
apple recommended they only buy gift cards from apple, but they still sell them in stores...
obviously money is more important to them than the consumers but pretending apple have zero responsibility is silly