A bad service and attitude towards a customer

Today (On the 3rd of June 2015) I bought a body warmer/jacket from pick n pay clothing at centurion Jean crossing (after I had been by centurion mall, kollonade mall, hatfield plaza and Brooklyn mall. I either could not find the colour or the right size). I then went to pick n pay super market still at jean crossing for a few groceries when I found the exact size and colour that I had been looking for. I asked if I could exchange the one I had just bought from pick n pay clothing, the lady that assisted me agreed. I went I fetched the jacket from my car and when they had to exchange I was told that they could not exchange as the jacket was a different colour (white). I was told to go for a refund then come back and pay for the grey one when I asked for a logical explanation behind this none was given to me. I was told they can't take it cos it's a different colour. After spending over forty minutes at the store I was able to exchange. My issue is why was I given such a hustle to exchange a pick n pay item at another pick n pay shop. I suggest that pick n pay clothing be given another name if pick n pay super market chooses to distance itself from it. Completely annoyed!