Around here it's very common, especially since during the winter we get less than 8 hours between sunrise and sunset. Even rides starting after sunrise in the winter need lights because of the overcast skies (similar to Indiana). The Seattle Randos start their short (200k) rides at 7am, mid (300/400k) rides at 6am, and long rides (600k+) at 5am, and for many we're finishing in the dark or riding clean through to the following morning. Riders tend to group up at night for safety.
The best taillight design I've seen is on a Corey Thompson custom randonneur: He built a Supernova E3 tail light head into a boss underneath the nds chainstay. From directly behind in a paceline, it's hidden under the stay so it isn't blinding the following rider. From a driver's perspective; 4 - 6 feet to his left and sitting considerably lower than a trailing rider, it's perfectly visible.