I can imagine a fast food executive looking at a number of charts, one displaying weight gain from exposure to particular products and one showing the frequency of visit to their outlets versus age.
"So, they basically stop buying from us at 56? Ok, so as long as it doesn't kill them before they get to 56, we make more money? Then let's do it!" (Everyone high fives). "...oh, and let's go ahead and start installing wide doors."