Hehe...I've run into some of those things in my life. I think they are a way of letting our minds try to control an uncontrollable situation.
My Great Grandma was *very* superstitious. I never new her, but her stories still ring in my mind. She thought snakes were the devil on earth. You had to kill them, chop their heads of and flatten them out (driving over them with a car a few times was good) before the evil was gone. If you didn't, something bad would happen to you. I can only imagine how she would have reacted to the pet iguana I had LOL