Why should there be nobody on the ground below? Other kinds of aircraft can fly over people. Quadcopters are much easier to control and stabilize than other kinds of aircraft.
All of these heavy machines in the sky rely on a ton of things going right at once not to collide... software, hardware, weather, etc.
It's a recipe for disaster.
There's a designated area where the aircraft do their show in and there are not supposed to be spectators in that area.
Airshow craft can fly over spectator areas but not when doing anything dangerous and if they are high enough.
The US actually has some of the most stringent airshow safety rules in the world, which is why most of the time when there is an accident that kills a lot of spectators at an airshow it is not in the US. Plenty of pilots have been killed in US airshows, but the shows are carefully planned so that if something goes wrong the planes should crash away from spectators.
I don't know if drone shows are subject to the same rules.
[1] https://www.faa.gov/about/initiatives/airshow/Air_Show_Speci...
If the article title didnt make it apparent, people can get seriously injured or killed when they plummet. Also I believe its illegal to operate a drone over humans without very specific exemptions.
Other aircraft are also inspected regularly and have regulations to follow, there isnt much of that for drones, any shmoe can fly their modified flying blender
- does not operate over non-participants who are not under a covered structure or in a stationary covered vehicle;
- will pose no undue hazard to other aircraft, people, or property in the event of a loss of control of the aircraft for any reason
The lowest category has this requirement too: Contain no exposed rotating parts that would cause lacerations
https://www.faa.gov/uas/commercial_operators/operations_over...