Not sure why that is. Is it even possible to switch back to an old name?
That reminds me, we have way too many zero post accounts here. Perhaps we should clean them up (delete them). All they are doing is using up good names that people who would actually post could use. I know this is possible. Zelda Dungeon does it.
Some of those accounts are for main site content rather than the forums, so no, they're not likely to be deleted unless they're really old. However, if there is a zero-post account with a name you want, just PM an s-mod+ and explain the situation. They should be able to deal with it for you.
@Acid: I have no idea what's happening. You may need to talk to Jason directly, assuming he doesn't see this thread.
*shrugs* I wouldn't know. I (almost) never pay attention to the main site. Regardless, every time this question comes up, Scott/Jason/whoever points out main site content as the reason. If that's changed at all, he forgot to tell Staff.