Using some kind of protection is a very good idea, especially when using the camera near salt water. Just consider this. Since the 30D is not water sealed, even if the water doesn't do any damage to the camera, if any of it gets inside and dries, leaving residue or, worse, corroding a wire or component, you will have a very difficult time convincing Canon that any future problem you encounter with the camera was not the result of you wetting the camera. In other words, if you encounter any type of problem with the camera during it's warranty period, you may have a hard time getting Canon to fix it for you under warranty if they see that there's water residue inside the camera.