If I had the time and patience, just for political protest, I would register in various forced-registration forums with an email created just for spam, and I would post a lot of spam in them, and probably something unwanted like hardcore gay porn, then after I got banned from one forum I would move on to the next forced-registration forum. But I would always post at the beginning of it an explanation like "I am only doing this because you are forcing people to register, I do not spam in other places". I have never posted spam, and I don't like spam obviously, but I would like if something like this happened. Just to prove that forcing people to register can't stop them from causing trouble. In that case it would have directly caused the trouble. Hopefully somebody who reads this will feel inspired and try that...