Air Ace,
Basically its sport as they all jumpers need to be a member of a club, and "purchases" are done through the club (in theory).
Where I see it gets very grey is advertising for services, that requires and AOC, adverts I see don't say become a member of a skydive club for one day and we will give you an introductory push out an aeroplane, rather "Tandem Jump thrill of your life" etc.
Some states clubs use similar rules to get around the liquor licensing rules, instead of buying say a beer, they purchase a raffle ticket from the club, you just happen to get a beer with the raffle ticket.