I believe Air New Zealand was the first airline to order A320s with Sharklets, so by virtue of this became the launch customer.
Hence the recognition as such by Airbus and the reason the a/c was at Le Bourget. Of course other airlines subsequently ordered a/c with the Sharklets and converted their positions on the production line to Sharklet a/c.
I hope this clears up the misconception and explains why there are already Sharklet equipped a/c out on line ahead of the 'launch customer' receiving their first a/c.