+1 because this is the elephant in the room. On all the other SE sites, the voting system works fine, and quality surfaces. If people don't want to be the "helpdesk for the intertubes", then they don't have to answer newbie questions, and those will be duped or whatever pretty quickly. I'm not saying admins all have flawed characters, but there's a power that comes from having root, which can corrupt, in the sense that all arguments spiral down to "because I'm the guy with root". This is an observable phenomenon, so I think this answer adds to the debate, if only in airing the issue.

OK - but that's something else. Allowing vendors to participate (and add value) vs. allowing them to use it as an advertising channel. Sure it's a fine line to walk - but for me, if a vendor is actively engaged with their community by answering or asking questions here, that's a good thing, even if having a thriving community is good for their marketing position. What the heck - we're all motivated by something, but as long as everyone plays by the rules, it's fine. The moderators can easily act against spammers, while allowing genuine participation to continue.