To put it another way: where i live, ads for cheese or meat are non existent (while ads for fast food or cigarettes are very common), and yet i know that those products are available on supermarkets or other food stores. And i can find cheeses and meats of many brands, qualities and prices on those stores.
I don't see how having ads for those things would be an improvement. In fact, i suspect that ads would be used to convince people to buy products of less quality, or downright toxic, as seen on the rampant fast food and cigarette ads.