they can... but the shortest distance from A to B is a straight line.
not possible in tennis with gravity, spin and all, but the closest proxy is a less curvy 'flat' ball.
you send a curve ball over, the other girl can run there and hit a flat back, now YOU are in trouble.
you send a flat one over, she maybe in trouble.
not to mention the nature of the topspin ball - has a tendency to land shorter than a flat one, even if the aim is deep.