I only feed one dog and get 6 weeks on a bag of food. I don't drink or smoke, I figure a few $ bucks more a month to feed my dog is money well spent. Could he do fine on a cheaper brand? No doubt. But when I tried Purina for 7 months he sprayed like a stucco gun and didn't do well at all. Switched to Acana and he is doing great. If the OP is having health issues trying a grain free brand is an easy solution if it works. When the top 3 ingredients in the bag are corn or brewers yeast and the dog isn't doing well my next choice would be to try a grain free option.