> Do you need advertising to tell you about bread, vegetables, meat?
Looking around at the world, yes?
Less-heathy takeaway chains do advertise constantly, and concepts like the food pyramid are there to literally "tell you about bread, vegetables, meat" as an advertisement for a better alternative.
People aren't born knowing this - if they don't learn it from parents, they will either learn it from someone else, or not know it and have a poor diet out of ignorance.
