ARE YOU SERIOUS? I assume you are, based on the rest of your post. My suggestion to you is don't go slinking around after dark on someone's dock. Walking up to the door and asking if you can dock for the night goes a long way. You can offer them some of your Skittles. A little courtesy could possibly have saved Trayvon's life, too. I guess we'll never know because the two stupidest people in Florida happened to run into each other that night, so all bets are off.
Actually I am serious, I would be very cautious in Florida. What would have saved Trayvon's life would have have been the psycho with the gun doing what the police told him to do on the phone,(to stay in the car and let the police handle it) instead of chasing after someone he had no reason to chase and assault. Had he done that he simply would have sat in the car and the police could have spoken to the innocent teenager and let him go on his way. The poor kid was assaulted by someone with a gun who was looking for any excuse to use it that he could find, I see no stupidity in that. To say he was stupid is an insult to him and his families memory of him. Bad luck yes, that is all. But I guess it is easier to blame the victim.
By the way I said even if the law said you could use the dock, (and that has not been shown to be the case) that you should still get permission. So asking permission is exactly what I said and that would imply courtesy.