I'd say they were donated. I doubt it would say "Promotion" on the sticker if the govt just bought them outright. And besides, when the govt wants a car for the weekend... do you think they have them all specially made to have all the extras and stuff? Idk...
I bet the govt didn't pay a penney, but I wonder who's idea it was... I'd still assume AMC, but seriously - there's no telling. It's just the way it's built to be more of an advertisement than simply a car, ya know? In my experience.... stuff like only happens when someone is really trying to "kiss @--" for a contract - and usually those things are freebies meant to intice.. but again - it's purely speculation on my part.