Well there is no argument as to who controls the airspace. That would be the government. Then depending on your jurisdiction the airspace is managed by a government agency. Sorry to tell you that you do not control the airspace over your property. Whether that is a suburban block or 800 acres of farmland. I do agree though that there will be some fun court cases coming.

In the USA.... https://diydrones.com/profiles/blogs...airspace-begin

In Australia.... https://www.gizmodo.com.au/2014/08/i...ow-do-you-own/

https://www.alrc.gov.au/publications...ons-property-1

you'd need to be more than a good shot. Even choking down and using Turkey shot that is a ridiculously difficult shot. Shotguns start not to work too well past 100 yards. Of course if the motivation is something other than autonomous skeet shooting and the true goal is bringing down the drone then there are likely to be better ways. For instance how about a drone or two hoisting up a lightweight 30 x 30 net...that method also gives a little more legal defense compared to discharging firearms, especially if the drones are over your own property.

You're probably thinking of Zipline in (currently in) Rwanda, it's a fairly scaled out operation:
Zipline ? Lifesaving Deliveries by Drone

In Europe the one to probably watch is Matternet (Working with Swiss Post) currently, and very much inline with the OP's theme:
https://mttr.net/

Yep, They are an impressive operation. Launching in the region of 20 flights/day and supplying 30% of Rwanda's blood needs outside the capital. It is impressive to watch a drone launched and immediately vanish into solid IMC, and then an hour later emerge from the fog and rain to a perfect capture, having dropped a load which has probably saved a life.

I believe the concept is more likely to get trialed extensively in the Military Arena. Food and Ammunition drops to forward units can be done easily and at whatever time is required.
May not seem like a lot but thinking you are in an outpost 15km from base, getting base to send hot meal every day while in the boonies can work wonders and reduces potential losses to IEDs. $5000 drone is a lot cheaper than a Medevac and medical care.

Arguement of could be shot down easily is sorted as self destruct mechanism built in..................... also if shot at then counter fire against firing area can be quick.

Proof of concept
 

This is an interesting proof of concept project. Amazon for example, pay a fortune to deliver their goods and so they and others are focussed on improving their already huge profits.

The insurance against risks and associated -ve PR conseqences of accidents may obliterate any advantage in terms of bottom line. IMHO a fair tax on such business should be a precusor to any further consideration of this delivery mechanism!

I think it will be a "2 steps forward, one step back" path, like autos. The tech will reach a point where proof of concept looks stellar. Drones humming along, model of efficiancy. Then one plummets to earth in a fireball, killing multiple humans, and the fleet is grounded. Insurance companies demand a fullproof software fix since they're defending multi million dollar lawsuits, and the media attacks this new exotic death from above. Then slowly the public gets used to the occasional crash, and the tech gets amazing, and it becomes the norm. But that's over a 15 to 20 year span we're talking about.

Hopefully the regulators are on the ball and the software / hardware / system design and implementation is up to a safety critical standard before it's allowed to operate. The omens are encouraging - a CAA representative attending a drone conference sometime ago underlined this requirement, so they're definitely on the right page.

What's happening in the auto space, particularly in the USA, is shameful; essentially they're proposing to put it out there and hope, and blame the human if it crashes. Given that people already treat Tesla's autopilot as fully self driving when the company says it isn't, one cannot be as optimistic.