I've very occasionally seen white poppies on people, and I knew that they existed, and I was pretty sure that they weren't religious, although I had to google to find out. I think that because it's the British Legion running the red poppies, it's not anti-war, so there is perhaps a distinction needed for people who want to say that they are anti-war, but not anti-those who died. Possibly. The article has confused me too greatly!