Public works departments already deal with a lot of bullshit from the builder's special trees that are already installed, managing permaculture forests would actually be easier in many ways. Portland Oregon handles this by making homeowners responsible for the sidewalk easement so they are encouraged to plant trees that don't get too tall and don't get too wide with their roots so the sidewalk doesn't buckle. So you get people planting a lot of fruit trees. There is a Gleaning group there that goes and gathers ripe fruit and does stuff with it like applesauce, or there is also a cider made by Portland Cider Company with juices from gleaned fruit they get off people's trees around town. It's pretty good cider.