If moderation tools are in the thread starters' hands, it may potentially cause unfair issues, like the idea of unfairly deleting messages, messing with the Points system by revoking points that users may deserve, and so on. We want to stick with equality; the tides might turn, things may become an issue if users are deleting posts that don't violate the community guidelines, and the equality we want may turn into inequality as there are people out there that might not like others or treat them "same" due to personal issues between the parties. This involves criticism too, people who might feel criticized might delete posts that may be helpful to others. It is just a snowstorm that I want to avoid. It would be useful, but it would also become an issue with balancing user points and unfair bias or inequality between the community.
Feel fee to report any issues though, when we logon, the first thing we usually see is that report because it notifies us. :)