The Only Way Dairies Can Survive Is to Go Very Big or Very Small

To lure drivers off Interstate 65 at Exit 220, about 70 miles southeast of Chicago, the roadside ads lean hard on wordplay. A metal corncob the size of a speedboat carries the words, VISIT EAR OFTEN! A sign with a cow on it promises A DAIRY GOOD TIME FOR THE FAMILY! Another billboard shows a wide-eyed kid with a fruit-flavored ice cream in his hand: BERRY TEMPTING!

You’re in for even more of this sort of thing if you take the exit. At the BP gas station, the little food market inside is called the Dairycattessen. There’s Central Bark, a ...