They are individual contributors atleast willing to contribute in some way to the free software movement. Images made with proprietary tools must have got into www.gnu.org.in by mistake, mostly because the site administrators didn't have time to check with pdfinfo and similar
I dont consider this as a mistake. We never rejected a code because it was written in Windows or Mac. They were contribution to us and we accept(as long as what they created is free). At the same time we wont use use nonfree tools for our work and encourge others not to. As i told some have offered to make new versions based on free tools.
I dont have anything more to say on this. Lot of work going on.
regards, arun.