You really are not listening to what I'm saying Cows.
Everything we do affects others.
When we drive a car we add risk to others who have not volunteered for the extra risk like pedestrians.
When I go on holiday and fly over London I am adding to the risk of those below.
When I buy anything at all, the aircraft that flew it in, the truck that drove it to my house. All these things are adding risk to the lives of others.
It is quite simply a part of life.
The actual added risk to drivers passing the airshow was infinitesimally low. Every now and then (once in 6 decades) very low probabilities happen. This is sad but absolutely no reason to ban something.
The whole point of making something a "one in a million" chance is to accept that risk. It will occasionally happen. You should not then say that it is unacceptable. You should turn round and say "well, we always knew it would happen occasionally" and continue. If it happens more often than expected then review. Once in 60 years is absolutely fine to me, and is an absolutely exemplary record.
If we start subjecting everything in life to the requirements already in place upon aviation we end up with the end of all literature, art, fun, civilisation and fun.
We all subconsciously accept that in life in almost everything but for some reason aviation is treated differently.