Woody wears boots in the opening scene. In the police station, he is not wearing boots.
After the family returns the Westerhoff's compressor, the boys get in the car. Woody is in the rear passenger seat. When the car drives away, the rear view shows his head in the driver's side rear window.
Driving I-90 from Billings, Montana to Nebraska, they should be traveling east. After they pass the sign for South Dakota, and the bikers pass them while passing large white satellite dishes on the left side, the view is to the west. Seconds later, with the sign for the turnoff to Mt. Rushmore, they are going east again.
When David goes to the Hawthorne Republican, the owner brings out large bound copies of the newspaper. At this point, the newspapers are at least 60 years old. Yet, the newsprint looks to be no more than weeks, maybe months old, not decades. In reality, the newsprint should have yellowed and be frayed, cracked, and severely worn.
David's Subaru Outback has its gas tank on the passenger side. When his father disappears to get a beer, David fills up the tank on the driver side.
The TV remote on Woody's coffee table is unique to Time Warner Cable. Billings, Montana is served by Charter.
At the start of the movie Woody is take to his home in Billings by his son. That house is actually located in Laurel Montana, 15 miles west of Billings (405 Cedar Avenue).
When David is looking at his brother's news broadcast, the "elapsed time" display on the DVD player is moving, which means he is watching a DVD copy of the broadcast.
When the Grant males are in the Hawthorne living room, presumably watching a Chicago Bears game on TV, the audio is the Bears' radio broadcasting team, Jeff Joniak and Tom Thayer, who never appear on telecasts. If they are listening to a radio broadcast with the TV audio down, it would be very unlikely to be so clear in Nebraska, and it doesn't look as if they are streaming the audio online.
Right before David picks Woody up, just after the scene with his ex-girlfriend, the traffic light he drives through is shown from his point of view and the top light is lit. The top light is the red light.