One should never mix culture norms with religion. Like for instance, women are not allowed to drive in Saudia Arabia but they are allowed to ride in taxis with non-mehram men.. Now if you take it in a Islamic point of view.. It is more safer and Islamically acceptable if she drove her own car alone instead of riding a taxi with a man who is not her husband, brother, father or son.. But then they have their own fundas of life which no one else understands.