That doesn't take care of the problem of having other people's
pages LINKED to my graphics. You can link to a graphic on another
site as easily as your own, the difference being that the server
where the graphic "lives" has to do the work of sending the image.
The typical parasite is a user who wants pretty images and doeesn't
want to pay the traffic charges for serving them up or doesn't have
room for them on their own site.
Less common it's a weaselly person who recognizes good graphics and
doesn't want to spend the time to develop their own.