To dream of people you feel are white trash may reflect feelings about yourself or others as being low class, cheap, or unconcerned with low quality behavior. A lack of concern for some area of your life staying unattractive. An area of your life where you feel other people prefer to behave without integrity or low standards as though it were normal when you feel it isn't. A lack of sophistication. Feelings about yourself or someone else being a "low-life."
Negatively, white trash people may reflect your feelings about other people preferring low-quality choices. Ignorance of improved possibilities or potential. A lack of sophistication that holds back progress. Low standards or low quality that scares you. Fearing being pulled down to other people's low standards of behavior. Anxiety about other thinking you are a "low-life loser."
Alternatively, dreaming about white trash people may reflect feelings about yourself having low standards and not caring about it at all. Some area of your life where you prefer low standards or low quality because it makes you happy. Accepting of yourself as a "low life." Not caring what people think of you.
Example: A man dreamed of seeing white trash people sitting on a porch that he drove past. In waking life he was trying hard to be perfectly abstinent for his religious training and couldn't stop masturbating to pornography. He felt like a "low-life" not being perfectly abstinent. and accepting this behavior in himself.