Expired product still on shelf, store saving a buck maybe?

I went to do my grocery shopping last week where there was huge saving special upon entry but to my surprise most items were not even available,which beats the purpose of the sale.I bought yoghurt as part of my items,yes I was negligent for not checking the BB but being a Pick n Pay customer over the years I’ve trusted any and everything I purchase,especially that which is belonging to the company brand. I bought my stuff on the 10th,had granola and yoghurt at work as my breakfast which I could not finish as I was put off by how the yoghurt texture was.The next day I decided to have the same yoghurt and as I opened it it looked frozen,it also had a sticky texture.Upon checking the expiry date it expired on the 6th of June which brings me to wonder why Pick n Pay would still have this product on their shelves. I must admit I was much disappointed and disgusted as it was my favorite yoghurt,more so a Pick n Pay brand which I do not think I will be buying anytime soon. I had obviously thrown the slip away as I didn’t think any of the products would give me a problem but it seems the Pick n Pay in Boulders Mall is not up to the standard it should be,mind you it was the first time I had shopped there. I’d rather go to Game really.