There is good news for Amiibo collectors, according to Amiibo News, since the re-release of Kirby's Amiibo, there is no longer aluminum foil under the toy of the Amiibo box, which means that the Amiibo can be scanned without opening the box.
The aluminum foil in amiibo's box has been designed to prevent players from scanning directly in the store to get the game prop reward without buying Amiibo, but it's unclear what made Nintendo change its mind, and Nintendo has never officially announced it.
Amiibo News speculates that since most people buy Amiibo as a collectible, amiibo is more valuable as a collectible than the game reward, so it can be scanned without opening the box, making it easier to save Amiibo.