Game Key cards have a banner on the box explaining what they are and marking them. They are IMO superior to a digital purchase in all but convenience. You can still sell, gift, loan them, require no Nintendo account to use either. And after the download to the console they work just fine offline.

Valve and Steam Works games happily sold literal trash that were useless to anyone but the first person who redeemed the key. They destroyed the second hand PC market selling codes in a box with potential time saver installers. And they still needed online activation.