The cashier or customer manages all that in your regular Scandinavian grocery store. The cashier has two "lanes" so two customers can bag simultaneously, if tha

The cashier or customer manages all that in your regular Scandinavian grocery store. The cashier has two "lanes" so two customers can bag simultaneously, if that is too slow they'll just leave a third pile up and close and hope it's a small order, or see which side goes fastest. Never a problem. For the few go backs the cashiers has a tiny stash. For the rare question you likely have to find someone restocking somewhere in the store and ask, otherwise their time is wasted. If you forget something, well pay and put the bag(s) by the cashier and go back in yourself. I guess someone sometimes are sent on cart-return or rebalancing. Though we tend to place those out by the cars so you grab them outside and then put them back by your car when done.