This is a dumb business idea but I don’t think something has to amount to a full-time job to work. This isn’t “Uber for dog shit,” it’s more like “Mechanical Turk for dog shit” (without the global cost-of-living differentials making it viable for most turkers). No one is going to drive or take the bus just to pick up dog shit, they’ll do it in their neighborhood or places they’d normally be, perhaps with their own dog. Hell, some people already pick up poop in their neighborhood for free, just to make it nicer. Maybe that’s where this idea came from.
I’m amused by the idea that someone might be picking up some poop but skipping others on a street because they don’t do it for free. Or maybe one dog owner “drafts” behind another so his dog’s poop gets picked up along with the first one.