Why do visitors comment my articles?

On my site http://learneasymoney.com I went to Settings -> Discussion Settings and under Other Comment Settings, I checked the Users must be registered and logged in to comment check box and the Comment author must fill out name and e-mail check box. However, when I see comments come up, I check the User section and the only user I find is the one I use to log in as administrator. I’m using a plugin called Pie Register to allow a user to register with their own password.

So why aren’t there any users yet there are comments?