Although I have not had any experience with Petco (my family owns a Natural Pet food store ), I have done my research and have had plenty of complaints to know what is going on. No matter what Petco says, It is not a Natural Health food store.
95% of Petco's foods and treats have the top 5 allergens in them: Corn, Wheat, Soy, Bi-Products and BHA. Therefore, if fed to your pet, they could go through many problems. This sadly, includes death, as seen in many reviews. Petco also has terrible customer service, and most of the Employees know nothing about Pet food, or your pets health.
If anything, they steer you to their most popular food: Purina. Petco ALSO Hires Teenagers to go to events, wear a Petco T-Shirt, and sell items to people, with little or no knowledge. To anyone that is wanting to find a healthy choice for their pet, PLEASE go to a health food store, NOT a big box pet store. Some Foods I recommend: EarthBorn, Zignature, Go OR Now, Natural Balance, Wild Calling, PureVita, Dog lovers gold.
They are all free of the top 5 allergens, and are extremely healthy for your dog. Do your research and consider going to another store :)