Having express self-checkoit is great. The Kroger near me went full-self-checkout. They have large kiosks that mimmic the traditional checkout belt kiosks, except the customer scans at the head of the belt and the items move into the bagging area.

If you have a full cart, you scan all the items, checkout, walk to the end of the belt, and bag all of your items. Takes twice as long as bagging while a cashier scans (for solo shoppers), and because of the automatic belt the next customer cannot start scanning until you finish bagging, or their items will join the pile of your items.

It effectively destroys all parallelism is the process (bagging while scanning, customers pre-loading their items with a divider while the prior customer is still being serviced), and with zero human operated checkouts running you get no choice