I don't think that, because there are no one to enforce it, we should jump right in and break FAA rules and national parks regulations. Otherwise on those lines and for instance, not having FAA enforcement agent near me I should take advantage of this and go fly like crazy high or in restricted places as much as I could. Responsible people fly responsibly, and don't need people behind them to constantly tell them what to do or not. Just my 2 cents.
A falling tree does not make noise. The falling tree displaces air that human ears detect as noise. If no one is around to detect it, the air is still displaced. So as to whether or not no one is there to hear it depends on your strength of hearing, natural amplification of the environment, and disruptions to the signal. e.g. a golf ball landing on grass does not roll as far as a golf ball landing on ice.
Just because you don't get caught at the time, doesnt mean you cant get caught later. If they have the ability to track your drone ID in airspace, they can get you later. They can also get you if you post the video on Youtube. And if your drone crashes and starts a fire or damages something you will be civilly responsible for all damages and cause problems for all drone pilots. Fly logically and responsibly.