Could it be that anything printed for the "flock" would be printed by the Christian Congregation of blah blah and anything printed for the "worldlies" would be printed by the Watch Tower Bible & Tract Society (or is it Watchtower? or are there 2 separate entities there also?)
The reason I ask this is I just read about some Catholic organization that used different letterhead when doing various business(!); the more religious letterhead when a religious outcome was desired and a more secular sounding letterhead if a secular outcome was desired...in true dub fashion, maybe they're just taking a page from their predecessors, especially if it suits their designs...