I don’t understand these “missiles cost too much” budget arguments. Defense costs hundreds of billions annually. The cost of the people who orchestrate the firing of that munition vastly outweighs the cost of the munition.
Have you ever seen the budget for the department of defense? Whatever they're doing here is less than the pocket change they lose in the Pentagon seat cushions.
Also, pilots generally need to fire a certain number of missiles every year just to stay in training. At least this saves the additional cost of a drone (the usual target for training missions, I think).
The USAF has purchased more than 10,000 of the AIM-9X model alone (not counting the other operators, domestic and foreign, and not counting all the other variants of the Sidewinder, the basic model of which has been in service since the 1950s).
