exactly; a colossal waste of taxpayer money
On the other hand, it could well be viewed as a big "stick it up your nose (etc.)" gesture to the kneelers.
Perhaps more likely, it is intended to remind Americans how seriously and how well we regard defense and security.
You have no idea what you’re talking about. These kinds of maneuvers for precision timing are very important for real time live situations. You never know when these practice runs will be the training necessary for an important event. Every practice run is important.