Its $20 million well spent to test defences systems. Just like the Soviets, the Chinese know that they are testing the defences and will avoid shooting for long periods of time until they penetrate to deep. Global Hawk is not there to see Chinese defence formation. That is done by Satellite which has the ability to see a grain of rice.
Once the missle is fired, Norad in under the Colorado Mountains together with Pine Gap in OZ will use triangulation to see the location of missile launch, speed, and the activation of various anti-aircraft defences.
The Chinese, the Soviets and countries like Iran, North Korea will use the event as propoganda to impress the ignorant peasant citizens of their powerful systems.
The Russians use the "Bear" to probe the US defences and the Americans will not show their hand but prefer to use their fighter aircrafts to intecept.
Welcome to the world of stealth and intelligence. You will not know how many dogs and how big the dogs are until you throw a cat in.
I rather think it is the reversed. That missiles' speed & technical data are already well known to everyone that can use google.com they will not use their latest missiles but just spend the near expiry date old stocks to QC the stock like in exercises and check weather their stocks need to be written off or can still be used.

There is no value to mark the radars nor the launch sites because they are just mobile items on wheels. 15 mins after shooting you they will be driven off else where for meals, and they are trained not to remain at the same spot once they exposed themselves. Otherwise they will be sitting ducks for incoming attacks.
What you pointed out applies when and only when there was latest prototype missile under test, and they need some intel.
There is nothing on the propaganda except Netizens STOMPed these. Govts pretended that it did not happened - both sides. And the tax payers had no idea about their US$21 million, congress may know with their hands squeezing on their own balls.
Drones are not challenging missile targets at all. They have no survival counter-measures to guard against any attempts to shoot them off the sky. The idea of using them in place of piloted plane is exactly to let them be shot down without a pilot killed or captured or need a search and rescue operation. Therefore no air defense commanders will spend any expensive assets to engage them. You send a $20 mil drone over I give it my oldest ammo inventory and let Intel team collect your wreckage, then file a report. I can not even expect to be promoted for shooting that down, only if I missed target may lose my appointment or sign 20 weekend duties.

:*:
Russian TU bears are different level of threats, it can carry some 5 to 10 strategic missiles each capable of few thousand km range and each may be multiple war heads. And it is not a drone there are 5-6 Russian pilots inside, so if you any how shoot, nukes may Accidentally Fallout over your head, and of not then Moscow will get the excuse of opening a war front for Increased chance of Putin winning this year because war with US means the sure need of a tough leader.

You shot a drone, you know that there is surely no pilot, not nuke on board. Just a pile of wreckage left after the bang and report to be stuffed in an archive and then business as usual. No news what so ever.
It will be a nice punk if Russian filled their radioactive waste from Chernobyl e.g. into their oldest (to write off) TU-95 and fly towards US or Japan, and pretend to have lost or emergency failure or pilot coupe. Lure the shooting. They will press the self-destruction button once the missile approach and shit all the radioactive contaminations on your people.

Weather your missile missed or not, you HUAT big time. It is your own fault not theirs, because the plane was on only routine training while having emergency, and they did not dropped a nuke on you, but you shot it over your own head to get the shower of nuke. They can demand you to pay for their plane.

