poor customer service

I had to stand in a long queue at mr price for approximately 30 min at this store and there were only two tills opened, not to mention the bad attitude I received from tshegofatso the cashier who gives an attitude when I ask her why two tills are opened instead of the whole 10 tills during peak hours, she said there is nothing she can do and I requested for the manager who never came after waiting for about 10 min, why there is no at least a manager or supervisor during peak hours, why the store does not give regard to customer service because all the staff walk around and are not bothered by the long queues