​I had a cool idea for a business, but it probably already exists.

So, you know self serve checkouts? What if instead of putting all your groceries in the shopping cart and then going to the self checkout, you scanned the items as you put them in the shopping cart, then paid before you leave the store, also at the shopping cart. This would be efficient. Im only 16 so I’m probably being real stupid here but I just thought it was a cool idea I guess.