Fair for Its Day: The rather incongruous song and dance sequence in the poor black ghetto near the racetrack. Nowadays we think, "They're treating them like performing pets!" But in 1937, it was actually pretty progressive to employ dozens of black actors in a major song and dance production. They were at risk of having the film refused by movie theaters in the South.
Values Dissonance: The whole sequence with the brothers pretending to be black is mighty uncomfortable today.