Disgusted by bad service

On Saturday the 31st of March 2018 my wife bought some clothing for our son at JET Eerste River. When she got home she realised that some of the clothing was to small and returned it the following Monday. She didn't see the need to take her Edgars card, because she's used to exchanging merchandise with only the till slip. When she arrived at the till she was told by the lady behind the till that she cant help her because she must have her card. She argued with the lady but the lady insisted that she cant help her without her store card. The lady than offered to keep the clothing till the next day for her to come and exchange. My wife was upset and walked out. Point is that we are working from Monday to Friday and by the time we get home the store is closed. Secondly, it was never a problem for us to exchange clothing as long as it was in its original condition and we had the till slip. Now we must drive up and down to exchange these clothes. We can only exchange the clothes on Saturday, now my question is what if we get there on Saturday and the sizes are sold out. I really feel disgusted with the service that my wife received and I don't feel like shopping there ever again.