One of the things I did to steel my will was to to think about the parents and the dog owners when I picked up other people's poop. However, thinking along those lines, I ended up connecting the idea that babies and dogs do not have free will, and I noticed that connection bubble to the surface when I saw homeless encampments. It colored the already dismal sight with a tinge of existential horror.
So, I'm not so sure that the baby/dog to encampment dweller connection makes the most appropriate vehicle for mentally dealing with the poop. Or, maybe, it is the right vehicle. I really don't know.