Yes, that's the one, thanks for finding it. The things are:
* I don't know exactly how such a locker works and whether OP cannot pick up the item, tamper it and then "post it" to another locker for the user (in my country the lockers belong to the shipping company and multiple sellers can use it). On the worse case OP can have a shop at Amazon and maybe he can get to use the locker. Of curse, it's a big hassle with small chances to catch somebody and steal his money.
* If the same problems like in that (Amazon UK) topic will happen, OP trust (which he may gain meanwhile) may vanish, even if it's not his doing
I see it a risky endeavor for both sides (yeah, trust is a bitch), but if OP gets customers for it, ... very nice and good luck.
I never thought of that attack vector. In the usa you can not open amazon lockers twice, but I could in theory still perform this attack. It would require me telling amazon customer service to give me a new locker code. This is possible and would leave a paper trail leading back to me. The lockers also have cameras on them. So if I drive to the locker you chose, tamper with the wallet and get amazon customer service to let me place it back in, I could in theory give you a tampered wallet. That sounds like a lot of work to just go to jail though, since this entire process can and would be traced back to me with amazon message logs and camera footage from the locker and business the locker is in. So although this attack is possible, I think it's not a reasonable fear to have. But what other people see as reasonable varies.
As far as tampering in general goes the only solution is multi-signature with different wallets. There is no other solution to prevent tampering when buying a premade hardware wallet. If you buy from ledger directly, amazon, or in person with cash at best buy, you face tampering issues. No supply change fix solves the tampering issue, and the only way to fix that is to go to the wallet manufacturer assembly line and build the hardware wallet yourself.
I have been a long time advocate of hardware wallets but hardware wallet manufacturers have shown a general disregard for their users safety by mishandling their name, phone number and email, in my opinion. So I made a service that lets you get a hardware wallet delivered near you without giving up any personal information.
however, at some point the customer will have to send you personal data for delivery, but how you can guarantee that all personal information on your app will remain hidden and forever locked from the public? I mean, instead to trust the HW manufacturer, why would trust your discretion?
Also, can you guarantee that your app is 100% hack safe?
I do not need any personal information from the customer for them to use my service. No app is 100% hack proof so I just don't collect information that could compromise your privacy. The only information needed for my service is: payment, what items you want, and the locker you want to pick up from. No name, no address info, email, phone number or any other information is used or collected by my service. So you can think of my service as guaranteed way to protect your privacy when you get a hardware wallet, something trezor nor ledger can offer you if you buy from them directly.