At least they use car mounted cameras and actually drive the car. Cracks me up on old movies when they’re doing front shots and you can clearly tell there’s a screen behind the car playing the background.

Anyway it’s probably just actors failing to act naturally. If you think about it when you first get in the car you always start with both hands on the wheel, then after going a ways you go to a more natural position. They get in the car put their hands on the wheel and director says action, haven’t been at the wheel long enough to get comfortable.