Just as a short aside, IIRC there is evidence that because of the very long association between humans and dogs, dogs actually _did_ evolve to make good use of some of humans' throwaways, compared to their wild relatives.

I don't have a dog, so didn't save the link, but for dog caretakers some literature review might do good (also, maybe consensus improved since then).

EDIT: obviously that doesn't necessarily translate to modern dry food.