But the display itself costs tax dollars, right? Wouldn't most Americans prefer to see their tax dollars used to repair crumbling bridges or to provide healthcare for those who don't have it rather than on some useless fucking circle jerk? I know I would.
Not really, military flight hours are programmed years in advance, those flight hours are being flown regardless of whether or not they fly over a football game.
As to the training value of the fly over evolution, it isn’t the highest level flight training but there is lots of good coordination, planning and flight leadership work that comes with doing a flyover. Purely from a “does this make our aircrew better” perspective, flyovers are not a terrible use of flight time.