I die on this hill for a different reason: the store holds the customer responsible for scanning or incorrectly scanning your merchandise. There was an article of a store calling the cops to arrest someone who accidentally forgot to scan something on the bottom of their cart.
Self checkout is a way for companies not only to get rid of a job, but to shift shrink liability to the customer.
If you're going to make me scan my own merchandise, then the store should wave my liability if I get it wrong.