Our world has changed a great deal since Ms. Givens wrote that anti-feminist statement in the 1940s. Since then we've seen the rise of our great economy. Oil, plastics, refrigeration, transportation, and feminism leading to a changing workforce have modified our way of life. Many a young and old person no longer have the skills or desire to cook at home.
-Meta Given, The Modern Family Cook Book, 1942.
I think the best reason for cooking at all is so that you can control exactly what goes in to your own food. In the world of peanut, gluten, and iodine allergies this is important, but also from the chemical and preservative perspective as well. You can actively control how much sodium, fat, and oil goes in the meals. You can actively exclude high fructose corn syrup, maltodextrin, MSG, sorbitol/xylitol, and other irritants. You can choose between organic or genetically modified, a choice somewhat lacking in most restaurants. Local versus imported. Food colored or irradiated. Fresh or canned or frozen.
My mother likes to cook at home to save money, but she also likes all of her recipes to be easy to make, so she tends to have a handful of raw ingredients and some pre-made ingredients in her recipes. Pancakes from mixes. Pies from canned, pre-sugared filling. Corned beef and cabbage made with canned meat. Store-bought ice cream.
I don't necessarily disagree with her philosophy in that it works for her and she likes doing things that way. It looks to me to be a generational issue, as lots of young women returned to the workforce they wanted to have their boxed cake batter and eat it too. I just think its a bit of a consumerist mindset, or lack of mindset, to think we need to have pancake batter to make pancakes is just silly. (Make babies and go shopping!)
It has been proven the nutritional content of every food declines with time and processing, except in the special case of fermenting. Freezing, canning, cooking, storing, dehydrating; all suffer some loss of quality over fresh.
The solution of the perpetual question of what are we to eat is simple. It's all about pairing foods to create a balance, then sprinkle a little bit of your preferences on top. Eat a variety of foods every day, it doesnt have to be expensive if you're careful.
Beans pair with grains, whole are more beneficial than processed.
Meat pairs with vegetables.
Dairy pair with grains.
Fruit in moderation.
It is almost always cheaper to buy unprocessed simple ingredients, like sugar and flour, in bulk.