Family Dollar complaint: Cashier

Just left this store where the cashier refused to double a customer bags which resulted in an heated argument where the customer called the cashier a name and the cashier was struggling trying to get him and swore to get him outside the store. The manager (a short lady with a wool hat) tried calming her but mainly indulged. Two male employees came from the back and helped escort the man out the store. On the outside of the store the customer asked the two employees did they see anything and they said they didn’t see a mothefing thing. I’m not understanding why the cashier (medium brown skin tone, brown locs). This is so disrespectful and unprofessional and it would be fair game if he seek professional business help in order to have something done. He left and she was still there cursing and the manager praised her for her actions.