How do you think most customers respond when treated unfairly in a store (e.g., being passed over for service due to race, age, gender or socioeconomic status)?

How do you think most customers respond when treated unfairly in a store (e.g., being passed over for service due to race, age, gender or socioeconomic status)? If a customer were to complain to store management about disparate treatment by an employee, what would you suggest the manager do to retain the customer? How should the manager respond to the employee?