Sure, but if you're this cynical you could also make a strong argument [1] that companies work, or fail to work, to improve the life/goals of the managers of the company. Shareholders and employees get screwed on a regular basis.
No private company even pretends to be serving "the market" either. That's the beauty of it, in theory. Nobody in the private sector is working "for" the private sector. And yet (in theory) it works.
Nothing democratic is ever serving "the interest of the entire country", if such a thing even exists. If it was, then why would such a thing ever need to be voted upon?
That the government operates in the interest of citizens is only what we say the government ought to do, which is not actually what it does. On the contrary, there are greater incentives for the government to operate primarily in its own interest, to increase the scope and magnitude of its power, which as can be easily observed, is what it has been doing.