And presumably some of the 66% are either children/students who have never had a job but will have a 401k or similar when they get one, or retirees who cashed o

And presumably some of the 66% are either children/students who have never had a job but will have a 401k or similar when they get one, or retirees who cashed out their 401k and bought an annuity (perhaps not the absolute smartest thing to do, but something a decent number of people do).