Rude security personnel

I went to Edgars Randfontein yesterday. After buying when I was about to exit, I was approached by a security personnel. She didn't greet me but instead said to me, "sisi i-plastic". What she meant by this is that she wanted to check the contents of the plastic bag with my purchased items. So I asked her what are the scanners by the door for. She rep**** that I must not ask her that and that she doesn't question me about my job. She was not polite in her approach but was very rude. She didn't even have a name tag on. My concern also is in the inconsistency of Edgars because when you go to other Edgars outlets such as Mall of Africa your shopping plastics are never checked.