Expired pet food on the shelves

On the 9/3/2019 I bought a pkt of Dr Hanz dog food for R67.99 from the Checkers in Blauw Mall in Pretoria. Roughly a week later I saw it was white and hairy. Took it back and after dealing with the extremely rude manager, they exchanged it for another pkt. Opened it in checkers and it was fine . Kept it in their pkt for freshness and 2 days later it was white and fluffy. When examining the package, I noted it expired 11/2018 already! Over and above the atrocious service by the manager, they have no concern for selling expired goods!