When I was a kid, we fed our poodles Gaines Burgers, Gravy Train (proud that we could add warm water to make a Gravy!), and Alpo... Amazingly, they seemingly thrived. The thought of feeding that junk now is unthinkable.
Really, I don't think any of the kibbles on the market today are the optimum food for dogs. They're either full of grains, potatoes, tapioca, or peas... However, I'm not willing to home cook for our dogs and I worry about the proper nutrition percentages, so I try to buy the best I can (a named meat product for at least 2-3 of the first 5 ingredients, and no corn, wheat, soy, or by-products - my dogs actually itch if fed ANY grains...). At least the scraps in the old days were real food!