Good and bad service

I went to spar to buy some groceries and the service I got was amazing from the cashier, she waited for me for a long time because I lost my card and she didn't complain at all coz she was about to knock off. When I went out the trolley porter gave me a bad attitude and it's not the first time I received some bad treatment from the trolley porters, I was very angry and he did not even care when I told him that I'm going to tell his manager, I think you should train them more, they do not know how to treat customers