I think there’s a big difference between riding in the back of a pick up and riding on the roof. The cab breaks down the wind current. I see nothing wrong with a dog tucked in safely in back of a pick up. I think it’s an American tradition, along with the gun rack in the back window.
If one were to put a dog on the roof of a car, why not put it on the hood also? Either place is just as safe when dealing with the wind current.
When a dog is inside, only its head and neck are out the window. The entire body is not subjected to wind which can dry out the skin/fur. Also, dogs are not 100% of the time hanging out the window. They come inside for mini breaks.
He didn't strap the dog to the roof of the car. The dog was in dog crate that he strapped on the roof of the car.