I'm a software engineer at Academia.edu. We have a feature which allows users to see which papers mention which users.

That feature is only available to premium users. During the first month, you can email us to cancel and we'll refund you. So users can test-drive the mentions feature, and if they decide they don't like it, they can cancel. We think it's useful, and we don't want users to be coerced into using it.

Also, we do make mistakes. Sometimes we mistake a user for another academic with the same name! But Google finding only one paper with a name on academia.edu does not mean that there is only one paper that mentions that name on the site.