If your just trolling by with no light shinning in his house and a quiet genny then **** that guy, like you said he doesn't own the water.
However it's a completely different story if you're fishing the same small stretch of river right behind his house. There are 2 houses withing eye shot/sight of one of my favorite spots on the river near my house. I flat out will not fish them at night. I've spoke with the game wardens and come to an agreement about bowfishing that stretch. As long as no home owners or farmers complain they will not hassle me at all, in fact they've encouraged me, turned me onto some new spots and giving me their business cards as a get outta jail free card.
The point of all this ranting is to thread lightly, void people as much as possible when bow fishing