Yeah, that's a common problem and it drives me nuts. We tried to pass a law here in Minnesota reserving the left lane for passing but it didn't make it. I didn't like the wording of the law so I supported its failure.
Here in Minnesota we have what is known as the Minnesota flying wedge. You can have 3 lanes going the same way and there will be 3 cars abreast of each other and all going the same speed. Miles of clear road ahead of them, of course.
I think the biggest cause of this is cruise control. People set their cruise and don't want to mess with it. They don't seem to understand that you can accelerate and not lose your setting. Or else, they're simply assh*les.
What I like to do is get in front of those people going slow in the left lane and then I start to slow down. Since the legal minimum speed limit is 40 I could potentially slow down to 40 and not get a ticket for disrupting traffic. Maybe that's what people should do as a form of protest. Pick a day and only drive the minimum speed limit. Let's see how those other idiots feel when someone else decides how fast they can drive for them.
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351W 89 Mustang GT Convertible