Pete recently joined as a follower of my blog. He's a young, athletic guy who commented that active folks and athletes need calories ~ more than the average adult.
That lines up with axiom: "energy in ~ energy out". Some Americans actually burn more calories than they take in, and so their nutritional needs are different than much of the population.
Seems like a marketing opportunity for those in the restaurant business ~ per menu options, or the entire restaurant's venue. Generally, Americans are unhealthy, and generally, they eat too much of the wrong foods. We have an obesity crisis ~ which translates into our health crisis.
Young, health-aware people like Pete will be always be able to seek out what they need without much trouble. I think there'll always be plenty of calories to be had, and most likely they won't eat more than they need.
That's the key. I'm betting people like Pete know the difference.
It's all about being aware. And restaurants, I believe, have a role to play in providing food options for those who are not.