I think a lot of the resistance to this is people are worried that the first-line treatment will be things like drugs, which can be expensive (to society, since costs are largely socialized even in the U.S. through the mechanism of health insurance) and have side effects. Look at, say, jrs235's comment ( https://news.ycombinator.com/item?id=5912203 ) elsewhere on this page. That's a valid concern. But obesity also comes with a lot of costs itself. If calorie counting is an effective approach, I think that it could address the problem in a cost-effective way. (And in a software way, too.)