This includes the sending of bulk e-mail. Protection of copyrights and trademarks. Some content is owned by others and is protected by copyrights, trademarks, and other intellectual property rights. It's very easy to copy things in cyberspace, but just because it's easy doesn't mean it's acceptable or lawful. Unauthorized copying of software is illegal, and you can be subject to criminal penalties beyond the termination of your membership.
Individual members are responsible for their own actions and postings.