Unprofessional behaviour by a Manager

Very Bad Experince I had on the 27th of April at Checkers Liquor Store(Silver Lakes) I was Concerned regarding the Que as it was not Moving with only one Cashier at the Till point, so I tried to Raise it with the Liquor Store Manager he then started to shout at me for no reason and argued with me in front of Customers saying that "we Customers don't know what we want and I can do what ever I want regarding the Matter" I was shocked and very Upset to be treated like that by a Manager, to a point that I had to Return what I had Purchased from the Store because of him, Nelson Mulaudzi is the Rudest Person I have ever come Across, I always Shop at Checkers Silverlakes or Checkers Menlyn but if that's how the Manager's behave!!! the Store Manager was not present I was then Assisted by Lesego who was very Helpful and managed to get another Cashier, I wrote an Email to Thinus the Store Manager no response up to date and it's almost a week I Guess customer service is not at the to of the List hey.