My own personal opinion is embodied in the phrase, "You don't stop playing games because you get old, you get old because you stop playing games."

I'm fairly close to retirement, and have friends who are getting there (or retired already). I really enjoy programming, and intend to continue indefinitely; most of my friends tolerate it as a job, and look forward to not doing it when they retire.

So it's the old "follow your passion" thing, again, I guess... I have that curiosity about such things, they don't.