Strake
I'm sorry but your argument does not hold water. You, and Satelite Driver, are trying to define something which in undefinable. And what is the point? All deaths resulting from air shows are regrettable. There has to be responsibility for all such deaths, whether of spectators or of passers by. How would you define a spectator? Clearly those who paid to go in. How about those watching from their own properties or from surrounding land, like Exnomad? How about passers by who pulled over into a lay-by to watch the display?
Deaths are deaths. There is no useful purpose in trying to define their quality. Indeed it is rather obscene to try and do so.