I came across the original photo, from Life magazine:
http://www.shorpy.com/node/4959?size=_originalThe one at the top of the thread has been cropped and the colors altered. If you look at the larger, linked version, the people don't look quite so white and skinny. It's hard to tell, but there are definitely at least three African American men and one or two women who might be, plus several people who could be Hispanic, not to mention a few chubby figures. Also they appear to have more diversity in age than the cropped version reveals, although there still aren't any really elderly folks. I see a lot of septuagenarians and octogenarians where I shop.