I don't know, to be honest "drive talk" isn't my forte but it does seem like some dogs seem to be actively on the search for food, while others are oblivious to the idea, and it seems separate to whether or not they're usually gluttonous pigs when you feed them. Obviously wild dogs would benefit from actively searching for food, treating that like a job every day would yield fruit so to speak. Some dogs seem to have this drive or instinct or whatever you want to call it strongly, while in others it is subdued or absent.