Because the goal of the government isn’t to turn a profit. Ideally, government funded needs should be used to create jobs in the country or region that government is in charge of.

If everyone switched to SpaceX for their launches, then they’d be handing a monopoly to Elon, and nobody wants that. Instead they need to be funding their own space program and drive down the costs to be competitive with SpaceX so they can be self sufficient.

It’s a problem that they need to use SpaceX right now, for several reasons.