Seeing as how there have been many driving scenes that didn't look so artificial I think that was an intentional style choice. I think it may have been used to show Rust having another one of his flashbacks.

After seeing how well he maintained his composure slugging whiskey and railing lines of coke/crystal/who knows what I'm guessing he is playing up the booze hound aspect to play the two detectives interviewing him.

I sure hope he ruffled your hair playfully before running back into the sea.