I didn't know we were having an arguement about wether or not kids made your life more complex. Of course they do. Underwear makes your life more complex. I simply was trying to explain, as asked, how my life with kids at home was simpler than my life with kids grown and gone.
First, I never disagreed with your ecological arguement. (Although, I think being a parent made my life less impactful, but not enough to compensate for the impact of even one of the humans I helped add to the planet)
and second, I said my life was simpler "in some ways"
yes, kids are more expensive than dogs. Hopefully they are around longer. No kids and no dogs are obviously even cheaper.
there are a variety of social and economic roles that I need other people to fill. Some of them used to be filled by my kids (we just hired people to do drywall. As a severe introvert this disrupted my life and stressed me out. Last time we did drywall, we used our home grown crew. Pretty sure it was cheaper, definitely far less stressful, totally on my schedule.) also, as stated, raising kids made it SIMPLE for me to avoid many societal expectations that I wished to avoid. Yes, I can still avoid them, but without the socially acceptable excuse, people tend to make it difficult and complicated.
so in some ways my life was simpler. It was also more expensive and more complex (although richer - like your food analogy). The complexities and demands of raising kids were for the most part more pleasant for me than the complexities and demands of being an empty nester in American society. I was only a childless adult for 5 years, and I was mostly in school or working poor, so no real useful data on my life there.