create a separate unedited chat area for those users than cannot be persuaded to use the site as it is intended - this would operate as a normal chat page so text would not be saved and there would be no one to cry to if someone is mean to someone else. Preferably i would make the answer bank compatible with this application www.gabbly.com (which whilst it won't work here at the mo will work on most every other site so other users might fancy giving it a go)
i would use this technique coupled with maybe some more permanent bannings to try and remove some of the groups that misuse the site to just chat to each other and give stupid answers to reasonable questions- which i believe puts off proper users and intimidates newbies that might have interesting questions to ask