The more important point is conservation of energy. Since the ground is moving backwards faster than the air, you can generate more thrust against the air for the same amount of power than the amount of backwards force exerted by the ground on your wheels (since power = force * velocity). For the same reason, if traveling upwind rather than downwind, you’d need it to use the opposite mode of operation - have a turbine driving the wheels rather than wheels driving a propeller.

Conservation of momentum is pretty irrelevant, since you have a giant immovable sink/source of momentum known as the Earth to push against