I think they do it for customers with bulky items that you can’t comfortably scan yourself since Costco self checkouts don’t have wireless barcode scanners like Sams so the employee manning the self checkouts uses their own that basically temporarily connects to whatever terminal the customer they’re scanning for. Very helpful so I don’t have to fuddle with big packs of paper towels or soda to try to scan their barcode on the built-in barcode reader. Kind of an oversight imo Costco… you literally specialize in bulk items lol the poor worker doing self checkout scanning assistance is always running back and forth between customers

At my Costco they have employees at every self check out. Pretty counterintuitive but eh. I treat it like a "10 items or less" sort of thing

They have the weighing thing, and then also the people who count your items at the door... so it would be hard to do. I think the thought was it's just more efficient to help if the employees are already standing there.