It would not be surprising if Starlink charged them 100x as much for each ms of latency boost. They would be paying not so much for the ms ahead of fiber as for their lower-paying competitors to get less ahead of fiber.
In fintech, they say "a microsecond is an aeon, a millisecond an eternity". You can do millions of computations in a ms.
Sure they will have many government including military, emergency services, coast guard, NASA and so on.
Starlink has many use-cases for the military they certainty didn't create it with that application as the primary goal. The primary goal is making money to fund SpaceX.