"Politeness" is one of the most widely used weapons against would-be victims of crime.
Remember, you don't owe anyone. You don't have to play along. You don't have to be polite. You don't have to keep your voice down.
If your gut is telling you there is danger, you listen.
Demand. Refuse. Make a scene. Be rude. Scream.
You don't owe anyone your safety.