I think I first saw those stills on a PBS airing around 1982, long before Warner or even Turner got their hands on the film. I never saw an actual print that had them, only video transfers.
My main lament with Gigi (it's not really a complaint if the source materials are shot) is the lack of texture and details in the background, especially Mamita's apartment. Take any shot in that apartment from the dirty old DVD and you'll see great detail in the fabrics and wallpaper where on...