In the 1970s, Dunkin' Donuts figured out how to market and sell the hole in the doughnut.
These were fun treats we would get back in the day. It's a shame there aren't many Dunkin stores left in my area as Tim Hortons are everywhere. I live close to the Canadian border so Tim Hortons are the preferred place of coffee and donuts people.
What's amazing, as some one who lives in the Dunkin plentiful area of Massachusetts, is that they are still a strong sale all year round. They are great when people bring coffee and doughnuts to work, on the weekend I often see people get a box at the drive thru. My wife even get then as a treat sometimes if we start the day early on the weekend.