Pathetic, useless manager who threatens customers

So we bought 2 packets of simba Mexican chili on 2 different occasions from the SPAR in ruimsig. Both packets the taste was horrible, burnt and had no flavour. I went to SPAR on the 9th of February to show them the crisp as I sill had some of it. When we got to the store we asked for customer service and there was no one to assist us. A gentleman by the name of Andre told us that he is not the manager but he can try to assist us. We explained to him about the crisp and showed him the slips and the fact the crisp was bought 4 days apart. The one packet of crisp he seen was expired. Note that packet was purchased on the 26th but the expiry date was the 25th. Fine we just told him that all we want is a replacement and to ensure that this doesn't happen again and should be taken up with SIMBA. As he was chatting to us a man by the name of Chancy walked up in a very abrupt manner and said that he is the manager and what's the problem. Andre then explained to him and also told him that the one packet was expired. He got very angry and started screaming and yelling at us and told us that how does he know that the packet wasn't from his store and that we are personally attacking him. Take note at this point Andre conversed with him so nowhere did we attack him personally because Andre pointed out that the crisp is expired. I told him it's not a problem I will prove that it came from his store and he started getting more angry and yelling at my husband and I. This all happened in front of other customers. Eventually the security guard came and tried to calm the situation down but this so called manager Chancy carried on to a point where he threatened me and told him I will see what he will do to me. Andre walked me to the crisp aisle and explained that they do not do refunds but will replace it for me. The so called manager turned around and screamed at Andre and told him that he should leave us and that we must get it ourselves. My husband posed a question to this so called manager and asked him so if I walk around now and go through every item of the store and pick up an expired item and bring it to him is it a personal attack on you as a manager or am I informing you that the store has an expired item. He turned around and said it's a personal attack on him. Firstly the way he handled the situation by screaming and yelling at us wasn't right, secondly he kept on throwing his position at us to a point that he stood higher than us so he could look down while we spoke and thirdly he openly threatened me. Is this the kind of management that SPAR Ruimsig prides themselves on. He boasted that he has 10 years of management experience well it's clear that he isn't good at what he does. I even told him that since the store has cameras I will inform the investigating parties to view the incident on camera to observe the manner in which he behaved that's besides all the witnesses that were present.