If you are posting photos that may include your fans on your Facebook Page, you want to make sure fans can tag themselves. It will help your page be seen. When a fan tags themselves it shows up in their News Feed with a link back to your Page. Then the photo is in their photos with your Page linked there forever.
There is a setting in Facebook Photos on your Page that is defaulted to not allow people to tag themselves. Watch the video to find out how to change it.