I was always led to believe that the Airpoints were forfeited whenever a member passed away. As an executor to my mum and dads estates, when I called to advise Airpoints of their deaths, I was never informed that the beneficiaries of the estate could claim the points.
Unless I am mistaken, when I signed up my own family for Shairpoints, I was aware that points earned by a member were forfeited upon their death. I have recollections of discussing this with my wife, as she had grand visions of using up my points.