The beginning of that episode where she gets surface access for mutants also illustrates covert racism pretty well.

The crew are at a charity gala for the university where mutants are trained as sanitation workers when Leela hears several of the wealthy donors making disparaging comments about mutants. She realizes they’re reinforcing the system that keeps mutants in the sewers while making themselves look good, and lets slip that she’s a mutant.

Then the hostess screams for the cops to toss her down a manhole.