WP roles and capabilities are reassigned for better control.  The
freeseat function admin_mode() checks for the 'manage_freeseat' capability.
This user can do anything related to managing a show, including selling
tickets, setting up a show, and disabling seats.  The exception is that
the freeseat settings page is reserved for a user with administrator
capability.  This way people in the box office do not need the
administrator role, and cannot change anything else on the site.