I know I've heard of people who get sick being sent home. I don't think they would undertake a long treatment process for someone who wasn't high up in the organization.
As far as living to be quite old, I would imagine the lack of stress in their lives is the major factor. Think about it...what do the rest of us have to deal with, especially in this miserable recesssion? If we can, we pay the high cost of insurance ourselves, and we worry about continuing to be able to pay it. If we can't afford insurance, we worry about getting sick and not being able to afford the treatments we need. We worry about having enough money for food, for clothing, for housing. We worry about losing our home. I can't even imagine what it would be like to NOT have to worry about these things. And forget vacations. We can't afford to get away from it all for even a little while.
The GB may be able to live like lillies of the field, but I can't, and it's probably aging me every day.