I feel that with dog foods, just like with human foods, there is bad and there is good. Just like McDonalds "junk food" versus cooking something healthy at home or even buying something healthy elsewhere - well, the same goes for our pets food. There is good and then there is the bad AKA "junk food". With humans and pets alike, there are ingredients in foods that we AND our pets can be allergic to, and I know because I deal with this with Tatum. She has horrible allergies and I do have to watch what she eats. Giving her corn and chicken would be a TOTAL disaster. Her having such bad allergies is one HUGE reason why she is on a Grain Free food with no chicken, corn, etc. Well - corn shouldn't even be IN dog food, period.
Sure feeding our babies "any" food will keep them ALIVE....it's food. However, that doesn't mean that "any" food is a GOOD, nutritious food. We as humans could survive on eating McDonalds too, it's food - it will keep us alive - but that doesn't mean that it's the right choice or that it is of good quality - or even more importantly, that it is HEALTHY for us.
In the end it is OUR decision as pet owners what we feed our pets, but I do choose to feed a high quality and nutritious food. One that isn't filled with corn, animal by products, etc. I am cautious as to what I put inside MY body, and I am just as cautious as to what I let my babies put inside theirs