It is not illegal for a manager to act like an ass and to verbally berate employees. It’s bad management, sure, but not illegal. The fiberglass trays are something that ought to have been reported to local health authorities and to the federal Occupational Safety and Health Administration (OSHA) and any similar agency your state has. If the trays were deemed a health hazard those agencies have the power to force the restaurant to change the trays. It is also not illegal for an employer to treat higher grade employees (level 4) better than lower level ones (level 0) by giving the higher grade employees better work assignments, etc.

What is illegal under federal law, if the employer has at least 15 employees, is to discriminate against employees on the basis of race, color, national origin, sex, religion, age (if the employee is at least age 40), disability, or genetic test information. Like many states in the South, Georgia has a very weak employment discrimination law. For the most part, it only bars discrimination in public (i.e. government) employment, not by private employers.

You have hinted that you believe that the treatment you received may have been due to your race. If the employer treated you and other black employees worse than others because of your race that is indeed illegal if the employer has at least 15 employees. In order to pursue that claim you must first file a complaint with the federal Equal Employment Opportunity Commission (EEOC) within 180 days of the discriminating act. Failure to do so will bar you from suing the employer in court. I suggest you consult an attorney in your state who litigates employment discrimination cases for employees and see how strong a case you might have, and do it quickly to ensure you can get a complaint filed within the 180 days.

Note that the fact that you quit might significantly limit your money damages if you sue the employer because you won’t have a wrongful termination case to make.