Dissapointing Service

I went to the Mr P Home Cresta Branch yesterday. I was at the till ready to pay for my items around 17:40. One of the female cashiers said, 'no one comes to the store all day but they all want to suddenly come when we are closing and cashing up' she proceeded to leave me and the other people in the line just waiting there and she left. Out of the 7 counters there, there was 1 guy assisting clients with something that took a while. I asked him if he can't call another cashier to assist and he said he was the only one left. When it was finally my turn it was 17:55! I feel this lady's comments were rude and uncalled for, especially in front of customers. Also your doors close at 18:00 so why is it a problem if was already at the till by 17:40. I work during the day and could only get to your store then,are we expected to leave our jobs early just so we dont annoy your cashiers by getting to the store by what she deems as 'late'?