Id checking can probably be done through the app. Most online bank accounts simply require a 30 second video call with a person showing their face and their passport and the account becomes 'verified'. You only ever have to do that once, so very cheap.
Restocking is already a cost stores have to do. Restocking is also something which isn't too time sensitive - you can do more restocking at night if needed. It's also possible to design the shop to require less restocking, by for example having deeper shelving units where products slide towards the front.
Helping people use the app won't be needed as soon as it becomes universal.
The only remaining cost becomes store security, but if everyone has an attached account which has been verified by a passport, even security might no longer be needed. Just bill people for the items they take, ban them if they don't pay the bill, and call the police and ban anyone who is violent.
Restocking is already a cost stores have to do. Restocking is also something which isn't too time sensitive - you can do more restocking at night if needed. It's also possible to design the shop to require less restocking, by for example having deeper shelving units where products slide towards the front.
Helping people use the app won't be needed as soon as it becomes universal.
The only remaining cost becomes store security, but if everyone has an attached account which has been verified by a passport, even security might no longer be needed. Just bill people for the items they take, ban them if they don't pay the bill, and call the police and ban anyone who is violent.