The reason is obvious to me. In anthropology, that's known as the "etic" or outsider view point of a cultural trait. The insider view point is called "emic," in case you're interested in trivia. Anyway, the holes make it easy to carry the fried bread chunks on a journeyearly trail food, in other words.
Lots of good info on his website.
http://www.castbullet.com/cooking/fbread.htm
Another reason for the “hole in the middle” is for even cooking. With doughnuts, bagels, etc., the outside overcooks while the inside is still doughy.
I make “fry bread” quite often for Indian Tacos. Especially for out of state guests, who are not familiar with our local Lakota Sioux treat. Instead of the hole in the middle, I just make the dough round very thin in the middle, with more thickness toward the outer edges. This way, when dropped into the hot oil, it cooks very evenly.
Thank you for the link, it will be interesting to me and is very different than the answer that hit me.
“Only God is perfect”, is heard many times in the west, so that is my first thought.
The Navajo rug weavers, leave a path or flaw in the rug, to also show that “Only God is perfect.
In the west, I do not recall having seen the fry bread with a hole in it, here it is served with honey or spread with beans and meat and used more like a tortilla.