I believe your good nature in this undertaking has been abused right from the start:
Indeed. That is what this community does and isn't limited to merit. If what you say is happening in this thread is true, then it is a very good example of how this forum is allowing scammers to make multiple accounts to abuse the system for their own benefit at the cost of generous members offering their time and resources to help others. If you think people are willing to go far to earn a merit, imagine the kind of nonsense occurring to get multiple accounts into the DT network to inflate their trust ratings and punish those who stand up against them.
Set a requirement to use only vanity adresses with at least 4 digits. Most likely that will help to prevent *some* fraudulent practices if we add more requirements (at least x posts, at least x registration duration etc.).