There are two ends to the true picture here - they do exist to protect and maintain the status quo as you say, but the underpinning (largely unspoken) assumption is that the general public, as the GP hopes, are among the set of 'those that benefit', on the basis that the continued existence and flourishing of the state is beneficial to the public.

That's the theory. In practice, of course, the truth has been weighted more to one side or the other at different times and in different places.