McDonald's opened a restaurant in Sierra Vista, AZ in 1973. Back in those ancient times, Army regulations prohibited soldiers from entering local businesses while wearing fatigues. That rule cut into the restaurant's business, so the management decided to add a drive-up window so the troops could be served without breaking the rules.
The window opened on January 24, 1975 and was obviously a huge hit. Next time you're sitting in your car and waiting in line for a large fries at 2am, thank the Army for helping create this towering symbol of American progress.
(thanks to U.S. Army W.T.F.! Moments Facebook page).