Impeeding traffic is a major hazzard and is ticketable in most, if not all states (check your state for applicable laws). Slower traffic to the right, if someone is driving so slow they have to have their hazzards on, it is safest for everyone for that driver to exit the freeway.
One thing this shithole state gets right is the "minimum speed" signs on the freeway. They're like 40, but if someone can't even go 40 they need to get off the freeway.
I used to carpool with someone who would get in the far left lane and turn on cruise control at 65. Not OK. I eventually started driving all the time and ultimately stopped carpooling with her.