It's rude to treat a customer badly.
Anita has been working all day running her clothing store and now it's closing time.
Anita wants the last customer to leave, so she can close up.
Anita asks the customer nicely if she help her out with anything because the store is closing soon.
Anita tells the customer that she doesn't have all day to wait for her, the shop is closing.
The customer accepts Anita's help, makes a purchase and leaves.
The customer is offended and leaves the store without buying anything.