I can't remember all the other boards, but I'm sure the auction board does not allow users to open self moderated threads, and as mentioned above, there are reasons why the privilege is disabled on some of those boards as it allows users to moderate their threads and prevent spam, although so many of the top threads (especially in the services section) does not use self mod option, as the OPs are highly trusted and any spam there would be easily noticeable as such.
Auctions are also in the Marketplace, not bad. Also, in that section, you cannot delete messages within 24 hours from the moment of publication. It would also be nice to turn off self-moderation as well.
There is also a notification of the number of replies deleted by the thread starter, which should serve as an extra warning to members.
When you damage your car on the road because of the pits, would you prefer to have this road repaired or to be given a map showing all the pits, thereby warning you?