I believe it depends on many mitigating circumstances on how the right holder should contain the rights.
If someone uploads their work to the internet, for non-profit reasons, and uploads it visible to the public. Than in my opinion that work is public domain, you have given the public access to use that work as they please and if someone uses it in a manner that you disagree with, you can talk to them and you can be against it, but in the end you uploaded freely. If however you didn't upload it visible to the public, have acquired a license of it or are doing it to make a living or for profit, then I believe you have access to safe guard your IP.
In the case of the photographer mentioned, I think he's a dick for holding the group photo for hostage, but if he didn't upload the photos to the internet for free and make them widely available, or he has a license to his work, then I believe he has right to safegaurd his IP and refuse access to other people accessing it. Others, however, could claim that they did not give permission for him to use their likeness in his photos, and any photos that contain them must be removed, or given freely, or else HE could indeed be facing a lawsuit of his own, though I'm not sure whether they'd have a case or not. So the guys a dick, but he can do what he wants, I just hope he doesn't expect to be called back to be a photographer for any furry events ever again.