neverendingjourney: Rutherford really left a mark on the religion.
Rutherford had connections with the family behind Coca Cola. I suggest that when he saw what advertising could do for a soft drink, he incorporated American advertising techniques into his 'revised' WT religion - hence his slogan. ( I think it was the 1938 Assembly).
" Advertise, Advertise, Advertise, The King and His Kingdom."