Because the missile costs a million dollars and now they can say that F-22 was in the first air-to-air combat.
It's all ridiculous, on purpose, first rule of military, burn money so you can demand more.
A few bullets would have been a slow descent they could track and capture far more easily.
Now it's a show they can reproduce a million dollars a pop.
The NSA is also now free to float balloons around the country for cellphone capture.