Some ex body builders turn obese in later years.

Pure health reasons. Putting on muscle is about the most health-promoting thing you can do (as long as you're not doing something insane in another area.)

elvismercury

mostly_harmless

The right real suffering

Yea, I see that too! I could do better on the weight training. 

My question with this is what do you do it for (other than aesthetics and ease of life)? 

For running, I have a race to compete in and a PR to beat, but it seems like weight lifting doesn't have as much of these events for casuals. Thoughts?