Journalists have ethical codes and so do librarians and lawyers. (Librarians also have a intellectual freedom codes, which might answer some of your question about why we can be so pigheaded).
Do Bloggers Share an Ethical Code?, posted at attorney Donald Vanarelli’s blog, is worth reading:
Excerpt: “According to a recent study published in the June 2009 edition of the New Media & Society journal entitled doing-the-right-thing-online-a-survey-of-bloggers-beliefs-and-practices, bloggers share a group of ethical principals. This first large-scale survey of blogging ethics identified four underlying ethical principles important to bloggers: truth telling, accountability, minimizing harm and attribution...” (link to full post)