My final comment is that I, too, received free use of various Polaroid camera models and free film throughout the years. Every one of my photos was paid for at standard professional rates. While my work was not part of the Land/Adams collection, one of my portraits -- taken with an off-the-shelf model camera and Type 108 Polacolor film -- was used in Polaroid's Annual Report for 1969 (in the company of such photo greats as Cosindas, Halsman and Karsh). For what it's worth, this was the way it worked with advertising and sales promotion. Of course, I have no idea of what deals were made regarding the Polaroid collection begun by Land and Adams.
Links to the record-breaking prices achieved at the auction.