DISGUSTING CUSTOMER SERVICE!!!!!

I purchased a pair of sneakers as a gift.I was offered a discount if I bought an extra item,so I did.I took them back to Sportscene Shelly Beach to get a bigger size.The only pair they had was the display pair.When asked if they couldn't get a pair from another store,they said they could,but I would have to pay R30 for courier fees.I am shocked!!It is not the amount but the principle!!!Why should I pay extra because you do not have the size I need in stock?!!!If I didn't pay,they weren't going to order the shoe,so I did.When I asked for my slip back,the person did a refund,instead of just giving me my slip so I could come collect the other pair when it came in.I was returned the discounted amount.When I asked if I would be given the discount again when the other pair came,the guy said no.So not only did I have to pay extra to get the correct size which you didn't have in stock,I now lose my discount and have to pay extra!!So instead of paying R950,for the R1000 sneaker,I now have to pay R1030,an extra R80.How many other customers are being ****** this way?I actually feel like not going back & getting that sneaker.I rather lose the R30 & buy it from elsewhere then pay extra!!