If you've ever dreaded the self-checkout at your grocery store—but found it to be a better alternative than waiting in a long, tedious checkout line—new retail technology could make the shopping experience faster and easier, and it might even save you money. AI-driven "smart cart" devices that attach to customers' shopping carts and scan items as they're placed in the cart are the latest entry in retail stores' race to automate the shopping experience (and collect valuable consumer...