I just operate under the assumption that everyone is going to make a mistake, it keeps me from getting too upset. Sometimes I have to remind myself that most people don't have any respect for the driving experience like we do. As everyone mentioned in this thread, basic highway etiquette is lost on people, maintain a stable speed, keeping right etc.
Okay here's my rant, if you don't know how to drive in the snow stay home or move South. I'm in one of the snowiest metropolitan areas in the United States historically speaking, it isn't a mountain pass somewhere in the Rockies and people have to actually drive to work. People are hopping onto the interstate and doing 35 miles per hour (no DOT plow in front of them even) in a lane that doesn't even have snow in a commuter car, and I'm doing 55+ in the lane that is actually covered in snow, in a commercial dump truck that's RWD. The area I live in is not some glamorous or nice destination, and it's not even that affordable at that. Don't like it, move south. Even just going to PA would probably be a benefit to some of these people who need a DOT plow in front of them always to feel safe. The worst part is they are locals who have lived here forever. But this is coming from someone who actually likes driving in the snow, so I have a distorted expectation of what speed people should be doing.