Expired products on the shelves

I could not believe it when I saw parmalat yogurt marked down to R9.00 at Pick and Pay Epping,something said I must check the Best Before date on the pack, to my surprise the park expired on the 27\07\2019. I took it to the maneger that was on the floor, he told me there is no mistake, that is why it is marked down, I was so shocked, how could they sell things that have expired, I mean what could have happened if I took that pack to my child, this is not accepted at all, how many things are we buying from this store that I not in good condition and we are not aware,as for the maneger to put products on the shelves fully aware that they shouldn't be there at all. This is so not on at all