On May 20, the first 100 customers at participating PetSmart stores will receive a bag of Nutro Dry Dog Food for free. (Scroll down to "What's Happening" to see this deal.) That's a savings of at least $13 and the lowest price we could find. Eligible flavors are Wholesome Essentials Chicken 5-lb. bag (pictured) or Limited Ingredient Diet Lamb 4-lb. bag. (Click here to find a store.)