I don't know. When I feel like I'm not in a rush, I stay in the right lane not because it's the designated slow lane, but because it's easier to get most of the exits which are on the right side. But a while ago, I started to take note of those guys that speed and weave in and out of lanes, and decided I wanted be more like them.
At first, I used to think that was only for the sportscars. Then I noticed it wasn't about the car, it was about the determination. New car, old car, sports car, pick up truck, Access-A-Ride Van (lol @ the fact that they drive around with stickers now that say they should be driving no faster than 55 with the phone number below to snitch on them
), it did not matter. Whichever lane was moving, they were in it. Wherever the space was, they fit in it. They were not content to simply be in the left lane simply because everyone in it is doing 65 with the limit being 55. They want to go 75. 80. 85. beyond.
I decided to style my driving after them - a little bit at least.
And I always thought passing on the left was for regular street driving only.