Why oh why is "Visibility: Roles" not working for admins?

I’m trying to hide a few custom blocks from only Administrators (Ads).
In the blocks configuration pages I’ve assigned the visibility to all roles but the Administrator.
No errors show up and the blocks configurations saves fine however the blocks are still being loaded when accessed by Admins.
What gives?

Drupal version: 

Source: https://www.drupal.org/taxonomy/term/22/feed