well-fed does not mean healthy.
Something interesting has happened over the last 100 years.
"Food" changed in definition.
"Nutrition" became a science experiment.
"Cheap, fast, and easy" became our country's motto.
"Done for You" became our way of life.
.....and our collective health has suffered for it. Especially that of our dogs (and any other animal who relies upon us to make their nutritional choices for them).