I would ask him about it. If your still not satisfied then contact the person on the deed. I can see why you would be concerned with the stuff going on out there but there could be a logical explaination too.
You pay your rent. You have no idea the situation.
The person you know could be a property manager or agent of the owner.
You can ask if you are curious but if you have been living there and it's not a problem, who cares.