Shoprite should teach staff how to handle customer

I was about to pay for my groceries at Shoprite Site C Khayelitsha. She did not even call me as she finished with the previous customer, instead she gave me a funny look. I place my groceries at the till point, she chatted to her colleague, complaining about why she was still at the till point at that time. I asked for a plastic bag and she said I was very forward, she was going to ask me herself if I needed one. The least I could have done is to shut my mouth. She complained about the time being 16:25 ans she was supposed to leave at 16:00. I asked her is it the reason she is taking it out on her customers, she said I was too forward hence the bad attitude. I was with my mother and she asked us to leave.