There is a limit how much you can ignore in the life.
Such camper sitting for long time will bring parking restrictions for all of us sooner or later. Do you still think it is not your business?
I live on at the end of the city, where lot of young people come for marijuana puff or beer drinking.
It might be all legal (is it?) but I own the only tree giving shade and I don't like the smell blown in front of my door, while common courtesy for beer drinkers is smack the bottles against the curb, or at the best - leave food packing on the street.
Sometimes - having 1/4 mile of empty street those drivers feel like parking in front of my gate :S