I'm not sure if it will save stores money or not. A lot of stores don't want it to be too easy to check out and leave. Getting to the cashier and waiting in line increases the chances that you'll make another purchase. Stores focused more on high volume convenience-driven purchasesprobably think about things differently though, and maybe they'd be more interested in something like this.

Maybe the bigger possibility is that it allows stores to present and sell their goods in afar more decentralized way that gets them closer to where consumers are. If on-demand workers, or drones, could restock inventory, and shoppers just needed an app to make purchases, then shopping malls could disolve into the surrounding cityscape.