God I remember when everywhere (even in school) was hooked on the "you are killing your kids with butter, eat margarine" line.

Of course, then they banned it most sensible places because of the hydrogenated/trans fats. Shocking that something made by chemical process by companies with large sums of money will be heavily advertised and pushed to people over, say, something that can't be patented by any one body.

Similarly, carb laden foods are cheap to produce and will last even if stored badly, you just have to try going out to dinner to an "average place" and try not to eat something where the dish is not mostly potato, noodles, rice, or flour based (pasta, bread, pizza base) to see why industry wouldn't think it was great if carbs came with health warnings.

Having said that, It strikes me from experiences in the past that everyone reacts differently to the mix of carbs and fats in their diet, but everyone seems to react to good amounts of protein, so while I'm not sure either should be demonised, clean sources of protein should be made more important.