From what I've gathered in talking with others on the issues such as these, the promoter has to enforce the sanctioning body rules of the track. Commerce is NHRA so you have to meet their specificiations, if not then (in the famous words of a FFW announcer) YAOUT!...
When I was running FFW Street Bandit since the majority of the cars were running 9's, all cars were required to have the appropriate saftey gear (cage, 3 layer jacket/pants, neck collar, gloves, etc)...
Luckily for me, I only need to get my chassis re-certified this coming year...