The world is, to some extent, what we make it. If we're going to make it better, we can't give up so completely; we have to have hope that the world can be made better, and that we're not alone in trying to do so. That's why I choose to assume that the TeamViewer developers are merely trying to make the best of the constraints they're working in, i.e. no proper way for a website to determine whether the custom protocol handler is already installed. In their situation, I would probably be forced to do the same thing, and I wouldn't appreciate such negativity. I assume you wouldn't either.