I’ve definitely had dogs that think they can never get enough food. They’re like Hoover vacuum cleaners and would suck up any bit of food as soon as it hit the floor. I knew it wasn’t because they were hungry, but you’d think they hadn’t been fed in days, so eager were they to consume every little scrap of food that came their way.
So, why do dogs always want food? Some dogs behave like that because it is built into their genes. Before dogs were domesticated and came to rely on people for food, they were scavengers and took their meals wherever they could find them. They ate whenever possible because they did not know when or where their next meal would come along. It was important to stockpile as much food in their system as possible in case their hunt was unlucky for a few days. Some dogs today still have that fear that the food will run out so they consume whatever comes their way. If you happen to own a rescue dog, it could be reacting to the memory of almost starving before you came along and still feels the need to eat whenever food is available.