Because there is a whole new set of rules about how and why you get admitted. Congressmen and Senators get yearly appointments providing the appointee can pass the physical and academic requirements. The criteria and procedure used to choose the appointee depends on the congressman and senator. Courts can't proscribe this sort of thing to the legislature. The children of admirals and generals can get appointments with the same physical and academic requirement and I think medal of honor winners' kids can get an appointment.