I think the way Fortune divides it (a number of programs use the terms interchangeably) is affiliate versus media buy.
I sure don’t see how media buys are that different – I do both and see little difference. Perhaps we are a bit more locked into a certain time span as per contract when displaying a media buy.
Certainly I would cooperate with a program’s placement preferences regardless of which way they got to be where I placed their ad, especially in as far as not wanting to be in a certain spot.