^ Images are traced by meta info embedded in the image — no secret there. Police and law enforcement always scrutinise meta data, especially if such images are being presented as evidence in court.
Once that meta info has been hijacked and replaced by something random, the image will not be located as rightfully yours. It makes me sick too, which is why I don't have a webpage. I've experienced image theft before (1999-2001 I think).
More reliable means of image protection are transparent gif overlays, black boxes... . Pointless tricks like right-click disable or Null-Save/Save to are also useless.
And the worst thing of all? It's that key on the top row of the keyboard that circumvents all anti-piracy tools. Can you guess what it is? We lose.