lucy24 - 10:00 am on Nov 25, 2012 (gmt 0)
Most hotlink routines use rewriting rather than redirecting, so the image will always come through as a 200. It just won't come through as the physical picture they asked for.
I used the "view site as googlebot" feature in GWT and aimed it at an image on my site that has htaccess hotlink protection on and they returned a 200 code which is good but does it return a 200 ok code even on the scrapers site despite being hotlinked since googlebot DOES visit image urls directly?
My point was that for google there's no such thing as "on the scraper's site". On rare occasions you get the googlebot (by name) asking for an image and giving your site as referer-- but what it needs to do is give some other site as referer. Preferably some made-up name that you can't possibly have whitelisted.
Come to think of it, what do you mean by "on the scrapers site despite being hotlinked"? It's either scraped or hotlinked. It can't be both.