I consider fetch, chuck it, ect... to be forced exercise. A highly driven dog will chase a ball until they physically no longer can. They are also not always very careful and will stop and turn suddenly, which is hard on growing joints. Also as a dog gets tired they get sloppy and less precise about how they move and are more likely to be injured.
I do play fetch with my dog as a reward during training, but I no longer use it to exercise them. If you watch an dog off leash doing their own thing you will rarely if ever see them running full speed in one direction, stopping suddenly and racing away again at top speed. If they are running at full speed they tend to do big looping turns and don't keep running at full speed for very long.
If all you have is a hammer, everything looks like a nail.