I've seen pipedope's beard posted on reddit before as well. That's how I found his journey thread, because someone put a link to the beardboard in the comments section.

When you post your photos on a public forum online they're pretty much open season for people to take and use as they please. It doesn't make it right but it's the risk you take.

You can always do a reverse image search in Google to see if your pictures are being used elsewhere online.