I doubt they'd spend much time at the airport ...

Even if you meant the city of Honolulu, that's like putting down NZ because you can't do much outdoorsy stuff in Auckland. Were they to choose Hawai'i, I suspect they'd head for Oahu's north shore or one of the other islands. While I don't know enough about NZ to compare the two for this purpose, the state of Hawai'i overall is not entirely unsuitable for a couple with their interests.