User blog comment:DaNASCAT/Technical Update: March 7, 2016/@comment-5558012-20160307231322/@comment-5558012-20160308002010

That last piece could of been taken two ways (still can): the Bureaucrat group itself is meant to contain Admin tools or users are meant to be part of both user groups if they are Bureaucrats. I clearly took that as the former which drove that original post. Thank you for correcting my mistake.

Edit: While Bureaucrats might not have many rights, those few rights they do have are very important to a wiki (including promoting Bureaucrats), which can easily stand as a standalone group from Admin.