Many customers will still want the human interaction. You fire all the cashiers, you lose those customers.Pretty much this but I'll take it a step farther. In small towns there would be no more grocery kids bagging groceries, everyone would turn into fully automated checkouts, instead of about half. Every fast food joint would be all kiosks. Mr robot also needs no vacations, never calls in sick, doesn't need health insurance, etc
Unless you're really believe companies are still employing them right now out of the goodness of their corporate hearts.