I wasn't crazy about the episode because the MotW, the Khan Worm, is really grossly disturbing. The episode has the Winchesters working with Cole to try to save a fellow soldier. This is also during the Mark of Cain run so Sam is trying to solve that for Dean who has a decidedly pessimistic view of the whole deal. Sam and Dean take the case as a distraction and only run into Cole later. The Impala's first scene is a night drive to get from the Bunker to the town where the case is located, Fayetteville, North Carolina. That is halfway across the US so the boys are on a road trip. The boys are driving in the rain and the drops on the windows catch the light nicely. The lights from outside the car add interest with changing lighting on the boys' faces. The scene ends with the Impala driving through the foggy rain.
The boys arrive in town in the foggy daylight.
At some point in the early part of the case, they run into Cole, or rather he finds them and commits a grevious crime. He leans on the car and he is not a Winchester. Shame, sir.
The Winchesters are NOT amused.
The thing about this scene is that the Impala is treated as functional scenery. She still looks good and she's a major piece of the scenery but she's not framing the shot or there to have gleaming reflections.
The rest of the scenes are handled similarly. She gets gas, drives at night, and provides a spot for a stakeout. First for both Winchesters and then for Sam alone. At the end, she's there for Dean to load up with gear while having a conversation with Sam.
She's a car doing car things and that is perfectly fine. It's probably how the boys view her most days as they go about saving people and hunting things. But Cole, only Winchesters sit on the car.