That's just my point. The water is not "the same temperature", it is cooler because it has passed through the radiator and has exchanged heat with the cold air that is passing through the radiator by virtue of the fact that the car is moving.Having the fan thermostat set higher - as high as 100 - is only a problem when the car is stationary, like in peak hour stop-start traffic. But that is generally only for short periods of time - as soon as the car gets up some speed again, the water will cool down to near the thermostatted temperature, even if the thermo fan has not cut in.
If you don't believe me, why not try it.