Food is a "very strong primary reinforcer" for some (not all) dogs. If the dog at hand does not care about them, they're useless for training purposes. Much the same thing can be said for many other primary reinforcers as well as many secondary reinforcers too.
I've never seen a dog that did not want to avoid punishment. Both reinforcement and punishment have a place in training dogs. It's impossible to train a dog without using both.
