While I agree that focusing your entire life around succeeding at your job is not the way to live your life, I disagree that you need to work just enough to be able to do the things that are unrelated to work. The comfortable balance point is different for everyone and, for the lucky few (which I count myself a member of), the things they really enjoy overlap substantially with their jobs.
The last time I was laid off, I had 4 offers on the table when I made my decision for the next position. I could have taken the position for a Wall Street firm making up to six figure salaries, or the position that was 9-5 and nobody ever worked more, or the one I actually took. Sure, I work some long hours (a 2 month stretch of 70+hours/week), but sometimes I don't. I get to solve some problems that are extremely gratifying to me both professionally and personally, which is a huge benefit.
When you're off visiting Europe, I'm figuring out how to reduce an hour long ingestion process down to 60 seconds by researching more efficient data structures and algorithms. At the end of the day, I'd wager good money that I got just as much enjoyment out of my research and implementation as your did riding around the countryside. Plus, I get the side benefit of it also being good for my career.