Rotten frozen pizzas

I am absolutely disgusted by Pick n Pay Jubilee Mall!! Bought pick n pay branded frozen pizzas for my son on 20 Aug. When we got to the till, the cashier started sniffing them and told me that it was because she had come across a few that were off. I still didn't think to check date on packaging. My son wanted to prepare 1 for school lunch on Monday...as he took it out the box the base is moldy!! Best before date is 5 May!!!! 2nd one he checked...best before date is 2 August. Why is old food not removed from fridges?? Imagine if he didn't check the base. I am livid that we are subjected to eat rotten food and I spent my hard earned money on it.