The self checkout is a perfectly viable option, so long as Walmart can find the strength inside themselves to open 3-6 manned tills on a Sunday for folks with large carts or children. Nothing is more demoralizing than getting up to the checkouts after a huge shop and finding there isn’t a single till open whatsoever. Throw in a four-year-old who wants to help scan every item and you’re ready to burn the store down by the time you leave.