The part from US 231 to SR 2 was overkill enough. Why go even further? While I supported the widening from US 30 to US 231 100% going all the way to SR 2 was not needed and was a waste of money. It's not that busy it did not need 3 lanes.
Can you post the traffic study you did to warrant that opinion? 
Just take a drive down there. Have you ever been there? Nothing but cornfields as for as the eye can see. The development stops around 231 by then you are out of Chicagoland.
Your traffic study had no mention of the road itself, just the surroundings.