alt Hacker NewsIt costs less, but it is not free. The stages need to be designed to come back and that adds weight. Additionally you need some fuel, it is not all air breaking. And every bit of weight is really bad, because of the rocket equation.
Without internal figures no one can say what is ultimately financially better. Especially now that the development is a sunken cost.
Yes, they should just parachute people out of planes, why reuse them thousands of times, carrying that extra fuel to land, they could go another few hundred miles.
The point is the ship and rockets are expensive vs fuel. Fly a Starship 100 times the cost is amortised over the flights and fuel+bit of refurb maintenance is tiny.