C'mon... you know that's not true. Maybe it's a regional thing or a geographic thing but I've lived in multiple US cities on both coasts and in the north and south and have had people use the term on many occasions. I even had a friend when I was growing up whose parents designated the role of "co-pilot" to the eldest when they were old enough to sit in the front seat.

"I need you to be my co-pilot and watch out for cops."