I have seen original graphics, text, and source code repeatedly copied and placed on other Web pages without permission. These are not a few isolated incidents but has happened dozens of times and continues to happen. It has even been done by several high profile individuals in the online genealogy community. Such individuals in particular should have known better than to steal from others. Most genealogists are very generous people when it comes to telling others about what we've found and we want to share such information with each other.
Voluntary sharing is the grease that keeps the wheels of online genealogy lubricated.
However, involuntary sharing does not encourage an open exchange of genealogical information. If you don't ask permission to copy a Web page element from someone first, you may be violating their copyright and stealing their property. Contrary to a common misconception, material placed on the World Wide Web is covered by international copyright treaties and the copyright law. The graphics, text, and source code found on the Web are not in the public domain simply because they are on the Web. Copyright laws protect almost any original expression or work when it is fixed in a tangible form.