Let's presume the maximum useful delivery is an iPad mini. That's 330g raw, call it 500g in box.
Let's presume that half of their 30 minutes is picking and prepping and that flight time is 15 minutes one way. That means we need a dwell of 30 minutes. Let's put a factor of safety of 1.5 - fighter aircraft lean. So we need 45 minutes of air time with a 1kg payload.
That cute little gadget they've got in the video is wishful thinking. You're talking DSLR-grade hexacopters and octocopters - a beastie like this with half its payload given over to extra batteries would just about do it.
So we're in the realm of "3 feet across" and "15 pounds in the air" and that cute little sussurussing of spinny rotors just became a screaming monster:
So yeah, you can do that, but no, it's not gonna just happen. The FPV guys have been dealing with this since the get-go: "we're just recreational hobbyists! Why are you persecuting us!" Well, the answer is you've got an angry wasp the size of a beagle ripping overhead at 40mph and it's fucking scary, yo.
Those are carbon fiber blades at 6000 rpm with a 500W motor behind them. Times six. The thing is a flying blender, it really is. I work with octocopters and hexacopters occasionally and yeah, they're cool… but they're fucking unsettling when they're overhead.
You think your HOA harshes on skateboards. Wait until they get a load of this shit.
I'm with 'em, BTW, and I own 3 RC helicopters.