tedster - 5:41 pm on Mar 4, 2012 (gmt 0)
This used to be an even bigger problem than it is today. Granted, it is a technical challenge for Google because many websites do host their images on other domains from the rest of their content - it allow browser to open more connections and speeds up the load.
Are these images truly hotlinked, rather than stolen? That is, do the other sites use mark-up like <img src="yourdomain.com/image.jpg">? If so, you can protect against hot-linking to your server and eventually things will sort out.