Puppy food per se might be thought of as a gimmick, but many higher protein kibbles on the market are not recommended for dogs under the age of one (particularly for larger dog breeds). Heck, Orijen makes a large breed puppy formula that isn't recommended for dogs under the age of one! Not everyone agrees about the safety of feeding high protein kibble to dogs that are still growing skeletally. Higher protein kibbles are relatively new on the market and there isn't enough research just yet to suggest one way or the other whether high protein kibbles are safe for growing pups. It all boils down to doing some research and making an informed decision that will best suit the dog.