Just to simplify to this single issue. In dense housing situation, there is no ownership of sewage, it is a shared resource out of necessity. You might say that everyone cleans out the sewer in front of their own house, but the guy at the start of the block only has his own to worry about where the guy at the end has the big pipe with everyones sewage going through it. Everyone needs to do their own part, but the parts are not equal by a long shot. Similar issues crop up in rural situations. If my neighbour doesn't manage his septic system properly, my well becomes polluted.
Justice is a nice concept, but in the real world it has to be managed through a legal system. Unfortunately legal systems are notoriously bad at dispensing justice.