Unfriendly bad service

Got to the chicken to order 2 rock my soul. The guy at the till Tumelo Thulare (who was not wearing his name tag. Thanks to the slip for his name). First he didn't bother to greet me, then as the transaction is going his colleague comes casually to start discussing a R5 coin now I'm left waiting for my slip and card. Eventually he gives me my card and slip no thank you, no smile nothing. Next customer after me clearly his friend, got a greeting, smile and thank you. I do not get why the treatment is different. Clearly there should be a note on the door that says if you are not the cashier's friend then don't bother to come in.