Гостиный Двор, ДЛТ и Пассаж были не department stores, а просто malls. Почему? Потому, что нельзя было набрать товаров в одном отделе, а заплатить в другом.
At the point of purchase, a clerk would rap on the counter and call, "Cash!" A cash child would spring off the waiting bench, pick up the money along with the goods and a sales check, and speedily deliver all three to the wrapping desk, where the cashier would tear off a sales voucher and make change. http://www.inc.com/magazine/19980615/1088.html
Bar code scanners?
http://www.inc.com/magazine/19980615/1088.html