I see the drones as a last mile delivery solution. Rather than flying the drones all the way from the distribution centers to peoples' houses, they could drive their trucks out to your neighborhood, and then release a set of drones to deliver packages the 'last mile'. This would allow them to deliver a bunch of packages at once without the driver getting out of the truck, and larger packages could still be hand delivered for the time being.

Also, I'd imagine that the drones would be (remotely) human driven at least the first few times they drop off a package, so they can learn where to drop off the package (similar to how Google handles training their self driving cars). After that, they could drop it off automatically, but hand off control to a human if the environment looks too different.