There's also nice psychological benefit to using a push mower. It's quiet! You can thus easily enjoy nature, listen to music or podcasts,etc. I've grown to hate using my power equipment for the noise alone.
My primary job right now is being a Dad, but once the kids are old enough I can leave them for brief periods, I might drum up some extra $ via lawns and other services. I enjoy physical labor, whether in my own yard or for $.