People may like it for a about a week ("neato, I can get my package lickity-split!") and then will say screw this, those things are making a racket and driving me batty.
It's not like they can be used to deliver groceries. And they presumably have to return to the base after each delivery, because they can't carry that much. That's just crazy inefficient.
I could see small electric rolling vehicles that make automated deliveries. But noisy little helicopter drones? Not going to happen.