All good points. But, the list of carriers that have gone through the hassle of being a participant in the program include a large number of carriers smaller than NZ, with small numbers of US departures, and/or with small numbers of pax that likely have gone through the process of enrolling in PreCheck. Allegiant, Volaris, even PAL Express, which doesn’t even fly to the US! Given how competitive NZ is with QF, I doubt it’s a cost issue but instead is a data sharing issue. Why oh why would Key Lime Air, GlobalX charters, and Air Serbia spend the $ to participate if participation was a financial cost to the carriers?