The best thing to do is to just ignore them. If we sticky the hate threads that will only embolden them and encourage more mud slinging. They're just trying to get reactions out of people anyway. If nobody replied to them they'd eventually get bored and move on.
After sitting here at work, sifting through all the threads to find something decent to read, I realized a flaw in your theory. If there is a sticky YES it would promote people to use it and continue to complain, however, its a persons choice to read it. Also for every person that we "Ignore" 2 more make a post and another fake one ie. ffxivtimesink appear to vent about their complaints, plus people are still replying to every new complaint thread that pops up anyway.