I am in West Texas, and people here say it is much worse than back east in DFW....
Now, on some highways, they do move over. I have been very impressed with that on roads in which you only have one lane to go on and people will move over. Very nice.
I am talking about I-20 and Midland/Odessa city limits.
I-20 is a major east west highway - many of those people you are claiming are Texans are traveling through the State.