Here is why: Many readers don't know that nonstaff writers (and photographers) sell a specific "right" when they deal with a publisher. (Staff writers & photographers are paid a salary and the work they create is "for hire" and thus owned by their employer, who can then republish it at will.) I freelanced in the 1980s and 1990s and typically sold "First North American Serial Rights," meaning permission to print something I had created - one time only, in North America only, and in that magazine or newspaper (a "serial" publication) only. Publishers of integrity, when doing a reprint, would contact me and offer a stipend for permission to run the piece again somewhere, maybe in a book, a collection, another paper or magazine, or a European publication. Not all of them had integrity - I had to sue a print publisher once, threaten a lawsuit against two, and write a demand letter to yet another to collect my agreed-upon fee and expenses - after they had used my work. With the advent of the Internet, print publishers began licensing the content of their publications to electronic databases or creating such commercial databases themselves. This brought them more revenue but they did not ask the authors (creators of the content they were reselling) for permission or pay them for the right to publish their work again. This was patently a violation of copyright law - a polite way of saying "stealing" - carried out by very big names in American publishing. (Click on the blue link above naming the litigation to see who the defendants were. You will recognize most of them.)
Genealogists - professionals and hobbyists alike - who write and publish anything (an article, a family history, a book, a web site, a blog, and so on) are authors in the sense this lawsuit describes. Imagine being a lone author and going up against the electronic universe. That's where a class-action lawsuit and guts was able to carry the day. So, thank you National Writers Union, Authors Guild, American Society of Journalists and Authors, U.S. Constitution, and our American legal system (expensive, but priceless.) And if you have ever wondered why I credit every source at the end of each writeup, and why I put warnings all over this site about not downloading and reprinting any image that is not personally owned by you or in the public domain, this is one reason why. It's theft, and from an ordinary person, like me and like you.