What 2 incidents involved cars this chapter? What role to they seem to play thus far in the novel?

It would seem that these really rich people can't drive their expensive cars well. *note the accident involving Owl Eyes.

Near the end of Chapter 3 Jordan Baker (the famous, and likely rich golfer) drives Nick (middle class American) around.

To the ultra rich, cars were a away of advertising their status. Cars also represent decadence and materialism.