Illinois wasn't the only state with turnpike plazas. Kansas had six, accoding to the back of this card. "These restaurants offer the finest in dining and have attractive gift shops with a wide variety of gifts and souvenirs for every occasion."
Seems like they got off the toicp of food a little too quickly there.
Note: despite the example of the man by the window, tuxeodos were not required.
The picture on the left is a detail from the Kansas Turnpike Authority's history page, and notes that the service at the restaurants was "so elegant for the region that many local residents drove out to the Turnpike for a nice family meal."
From the looks of the contemporary info pages, they're mostly chains now.