In the future, robots will move your shopping cart in stores. Take Dash for instance. It is a robotic shopping cart that makes your shopping experience more fun. Simply walk up to it, provide your shopping list from your phone, and let the robot find the best route to your items.
Dash has a scanner and payment system, so you can scan and pay for the items in your cart. The robot follows you to your car for unloading. It has a virtual reality interface too.