Kelly Brownell in the Wall St Journal points out that today "healthy foods cost more and calorie-dense processed and fast foods cost less."
This is partly because of subsidies to high fructose corn syrup and other sugar-laden and corn-derived industries.
It is also because healthful foods without preservatives may not have as long shelf-lives as artificial junk that can outlast a nuclear event – and which don’t need to be replaced as quickly by retailers, say compared to fresh fruit.
And it is also because nowadays so many manufacturers use pastes and emulsions that they purchase with fillers and mystery ingredients you can’t recognize – and which tend to be cheap artificially derived materials that are high in carbs but of empty (or harmful) nutritional content – i.e. HFCS, corn fillers, pastes made of fruit syrups like dates, hydrogenated oils, and to a lesser extent soy fillers, etc.
Look at the ingredients in the back of your product – and watch out for these.