The self-service checkouts is a good point - but in my experience at least 10% of those are regularly out of service, and they are large systems that are meant

The self-service checkouts is a good point - but in my experience at least 10% of those are regularly out of service, and they are large systems that are meant to be robust. I can't see how that will scale up to thousands of product lines. As you say though, the staff will probably be far more busy replacing items...