I work as a "board monitor" at a major Internet service provider (ISP). That means I make sure that material posted by members of the public on our online "chat" board isn't offensive, illegal, or against our company policies. Lately I've had to remove a lot of copyrighted articles that people have posted because they put up the whole thing, word for word, even the copyright logo. Isn't this still a copyright violation? What do I tell these people when they yell at me?



Posting entire articles is a copyright violation, and you are definitely doing your job by removing them.
Your company is no doubt trying to carefully follow the Digital Millennium Copyright Act (DMCA). The DMCA basically says that ISPs can avoid copyright liability only if they get no financial benefit from copyrighted material, aren't initially aware of the infringement, and remove or disable access to copyright-infringing material as soon as they find out it's on their website. An ISP that doesn't follow these rules could find itself sued directly by the owner of the copyright.
What to tell the folks yelling at you? Try appeasing them with the following alternatives: