Slow Traffic Keep Right!

I'll admit I tend to drive within the top 20% when it comes to highway speed, but only when traffic allows. I grew up in times and places where it was understood that, unless you are actively engaged in passing another vehicle, you stay in the right lane. I am now commuting on a 4-lane highway that I used to drive daily about eight years ago. Back then, it seemed rare to see cars lined up in the left lane, with the right lane clear, but nowadays, I see examples of what you see in this pic more than anything else.

I have come to the point where I can accept people hanging in the passing (left) lane, until someone approaches from behind, at which point, you really should move over to the slow (right) lane. Driving slow in the passing lane prompts people to pass on the right, which is more dangerous than passing on the left. And if I have to go into why that is, then stay home and don't drive. At least stay out of the passing lane unless you're passing somebody!