Ethic, should we adopt this disclaimer that the internet is not safe? Neither is your favorite MMO:
The other people on the web, including other visitors, our employees, agents, and guests, and anyone else who might sneak in, may be stupid, reckless, or otherwise dangerous. They may be mentally ill, criminally insane, drunk, using illegal drugs and/or armed with deadly malware and ready to use them. We aren’t necessarily going to do anything about it. We refuse to take responsibility.
It is much like rock climbing in that way.
Big hat tip to Overlawyered.