I would gladly pay (perhaps just a little, but I'd certainly pay) an NGO that helps citizens of my city that have lost some dogshit, to retrieve such dogshit.

It would maintain shit <--> dog <--> owner <--> known addresses gathered from public sources and have scout teams that find dogshit, identify its owner, and send it to them on a nice little package; perhaps one of the addresses is their workplace, which is so convenient. Or perhaps there can be an app for geotagging lost feces...