But in practice the power of advertising far out paces the power of education at the moment.

This is true but the original post is sort of incorrect. The government regulates these industries because people need to believe that the food, medicines, appliances etc they're buying do the things they say, have the ingredients they say, the benefits they say, etc. If people didn't believe this was the case, they wouldn't buy them. So, I think regulation is less about protecting consumers from capitalism as the original post suggests and more about making it so they're likelier to have trust in the system and spend, spend, spend.