diberry - 5:32 pm on Aug 7, 2013 (gmt 0)
I don't expect Google to somehow detect piracy before it happens, or to always recognize it after the fact. But once NOTIFIED that Site A is pirating, I believe Google has a legal duty to drop them out of the SERPs and possibly cancel their Adsense account as well.
That's why I was suggesting you notify them that these sites are pirating your fonts, and include any documentation you can to show that you created the fonts and/or designed them first. (If you can't attach the documentation in your first contact with them, just describe what documentation you have and ask how to send it to them.)
I don't know if the following is typical but I have one page scrapers just adore. I used to check the SERPs every couple of months and send Google DCMA notices about all the ones that had stolen my page. Now I get trackbacks from scrapers but can't find them in Google. At least in this case, it looks like once Google can "recognize" a page that's particularly loved by scrapers, they do get better about not indexing new scraped instances in the first place.