That may be the point - if it's the sort of company who will hire (frankly) just about anyone to do the basic jobs, the people supervising them are even more important. If you hire somebody basically competent to look after a checkout, you can just let them get on with it. If you hire somebody who's generally not very good at things, they might well make the sort of mistakes that leave you asking 'how would anybody do that?' if left to their own devices. Picking up the military analogy I made earlier, that's certainly true of soldiers!