Just heard about this on CBC when they interviewed Simon Berry.
Essentially he was working in very remote places in Africa, yet could always find Coca Cola for sale. This in places where basic healthcare was not available for kids. Only 1 in 5 was making it to their 5th birthday. Many died from diarrhea. He hit upon the idea of using the “dead space” between the bottles in the Coca Cola crates to piggy back on Coke’s distribution to these places without increasing transportation costs. Enter a very cleverly designed packaging to fit between the bottles.
Then though, it became apparent that the real driver was simple capitalism. Make it worth the while of all the distributors, and create the demand, and voila! Retailers were ordering the kits by the box-load – whether they went with Coke or not.