I think DTM is right and it's more of a private feature.
Here's the info from the help for those who don't know anything about the feature:
What are my Friends and Foes lists?
You can use these lists to organise other members of the board. Members added to your friends list will be listed within your User Control Panel for quick access to see their online status and to send them private messages. Subject to template support, posts from these users may also be highlighted. If you add a user to your foes list, any posts they make will be hidden by default.
How can I add / remove users to my Friends or Foes list?
You can add users to your list in two ways. Within each user’s profile, there is a link to add them to either your Friend or Foe list. Alternatively, from your User Control Panel, you can directly add users by entering their member name. You may also remove users from your list using the same page.