&& I agree, they aren't useless, obviously, some people have the brains to think "Oh, I bet I could put a O-ring on it and fix it" and its free. Soooo, guess if you think they are useless, get on to the next post to troll on. Thanks!
@Dyingflowerchild you've obviously never lost the back to a plug before. Just like xxmishaxmurrder and AmberNNTaylor said, you simply use an O ring. That's a no brainier! ;)