On the contrary, art has intrinsic value to those who experience it. Why commission public murals, Why commission public statues and sculptures, if art has no intrinsic value?
Because it has subjective value. And often times those public pieces aren't there to showcase art for arts sake, but as a showcase of how much the politician cares about the community. In a purely theatrical way, of course.
And, depending on ones own interpretation, assigning intrinsic material value to art reduces it's value as art. Making it less art and more commodity.