Customer service non-existent

A few days ago I bought a shoe at Riddz footwear(Golden walk, Germiston) I got home and the shoe was uncomfortable. I went back today, 27th September to get the right shoe size but they were out of stock. I looked for something else to exchange the originally bought shoe for but couldn't. I was advised I couldnt be refunded as it was a sale item, I had already looked around the store and had found nothing I liked so I asked what my options were, the lady who was at the till and assisting me told me I had to wait til they got new stock, I had no problem until I asked her when they'd get new stock, in a very rude way she responded she didnt know and that I had to either take the shoe with me, take something in the store or wait til whenever they'd have stock. We ended up getting into an arguement, shen 2as shouting and just plain rude thn proceeded to tell one of her colleagues to close the doors as she wanted to close up. I was left standing there like a fool but before that she told me I could do whatever I wanted and it wasnt her concern. I'm utterly disappointed at the poor customer service I recieved. I left the shoes there and my money has basically gone down the drain