incrediBILL - 1:31 pm on Jun 3, 2012 (gmt 0)
This type of activity has been going on for a long time.
I nuked all my images in Google's index search, that was a few YEARS ago, just to not be associated with the nonsense going on and shortly afterwards they started hot-linking direct from my site! Pretty easy to spot a bandwidth spike when you have 40K+ images that suddenly get hot-linked.
I quickly installed anti-hotlink code in my .htaccess file and have left it that way ever since.
Why Google doesn't simply use the same anti-hotlink code to block them from doing this is mind blowing IMO. Google seems to go to extremes now to stop scrapers from ripping off their SERPs but images don't seem to be an issue for them.