Often, dogs can get so excited by the sound of the refrigerator door or your presence by a food location because they know what's coming next - a delicious treat! Because the treats are hidden the rest of the day, there's a certain novelty and excitement associated with this event. Your puppy's enthusiasm can be so overwhelming that he just can't think about anything else! The novelty of the treats being available all the time will wear off, and your puppy will eventually ignore them.