You move over. A little courtesy won't kill you, and it's the right thing to do. If you're not passing anyone, and you're not in stop-and-go traffic, you have no business being in the far left lane.
I’ve made it a habit of thanking any driver that moves out of the way if I am faster (friendly hand wave), and in turn, to get out of the way of drivers that are faster than I am.
I’m honored to share the road with you.