How about this -- there are healthy people whose jobs are so demanding that they basically gradually lose their health (physical and/or mental), unless they can find a way around it. (Usually the way around it is quitting in my experience.) If they don't, a chunk of the (often substantial) salary they make will go towards medical expenses every year.

It actually takes quite a bit to be healthy and stay health in modern society. If you are healthy and are in a relatively good position in life, then, alright, you're directly responsible for maintaining your fitness. But there is a lot of medical problems and life circumstances that aren't visible. So if you can hit the gym everyday, count your blessings and don't take that for granted!