If you remember, for the LONGEST time, there was the issue of spambombers in the review boards. So, at that point it was always told to people to prevent that, you have to disallow anon reviews. When recaptcha was added to the archive, this became a non-issue, for the most part, because the spambombers HAVE to enter the text for each and every review left. As it changes with each review to be left, these spam scripts can't quite manage it, LOL. If I remember right, disallowing anon reviews is the default setting, so when you add the story, you have to check the box saying it will be allowed.