Hmm, Seeing the layout (having never been to the races myself) brings to mind the wording of the Canadian regulations:
Air show aerobatic manoeuvres conducted inside the aerobatic box that have a descending recovery with a pull or push and having a flight path which, when extended, would contact the primary spectator area will not be approved for inclusion in an air show.
The Reno races (though I agree they are American, not Canadian) are not an "airshow" you say?...
"air show" - means an aerial display or demonstration before an invited assembly of persons by one or more aircraft;
The races are not "aerobatics" you say?....
"aerobatic manoeuvre" - means a manoeuvre where a change in the attitude of an aircraft results in a bank angle greater than 60 degrees, an abnormal attitude or an abnormal acceleration not incidental to normal flying;