All the underwater reefs in the world are endangered from many things, including human beings walking on them. So when you take a surfing lesson, go swimming or for a free surf, don’t wear reef shoes. Besides making it hard to; balance on your surfboard and swim, they not only make you look like a kook, (surfer slang for very uncool) reef shoes crush the reef when you walk on ocean floor with them. It’s much healthier for our friends in the ocean for humans to not touch the reef at all.