More than likely, its a lack of understanding on my part. But my assumption is that the wallet key is for valet use, and if that's the case, then why do I need to give them my code? I would imagine the simpler idea would be that if there is no authorized phone or key fob in the car, and only the wallet key, then the car automatically goes into valet mode (lock gloevebox/frunk/trunk access, and maybe limit speed). In case my phone dies, and I have my wallet key, then I can input my code to get access to glovebox/frunk/trunk.