On the other hand, I don't spend large parts of my life exercising and worrying about my health. Why spend 30% of your off-time to perhaps live 20% longer? Especially if most of that time is going to be in a retirement home, worrying about bowel movements and whether there will be pudding.
In no particular order:
* The person who is fit/healthy is less likely to end up unable to wipe his own ass in a retirement home.
* Fit and healthy people get more attention from the opposite sex.
* Exercise is a natural anti-depressant.
* Exercise boosts libido.
* You'll sleep better.
* You can eat more.
Of course there are no promises. You could be in the best shape of your life and get hit by a bus tomorrow. Such is life.