That "inevitability" stems in part, from economics and in part, culture. I think that you're right that cultural enlightenment won't fix the problem, at least not without the economic side. Unfortunately, as part of the cultural side (in America most especially) efficiency at the cost of all else is prized, much to our detriment at nearly every level of our society. This means that the people employed to engineer junk food do it well. They do it as efficiently as possible so that their company or corporation can most efficiently make money. Thus lubricated by the warm, lipid embrace of highly engineered foods, many people slip down the long slide toward death. Efficiency and morality are often at odds, because well, doing the right thing is all kinds of inconvenient, time consuming, resource draining. In a word: inefficient.