It's just something that I saw, and thought was a bit strange.
One year, on the Elephant Rock Century ride, the 60-mile support stop was in a park at Palmer Lake. We rode down a long hill, on a county road, and then we were direct to turn left. The rest stop was located about 100 yards off of the road, at the end of a gravel drive.
Carol and I were riding together at that point. She was on her Specialized Allez road bike and I was on my LeMond Zurich. We both were running 28c tires, large by road racing standards, but the narrowest tires I ever use. Still, riding up the gravel drive was no problem.
We were both somewhat amused to see people get off of their bikes and walk alongside them on the gravel. Some of them were even grumbling to each other, as we rode by, about having to go off pavement to get to the support area.
The capper was when we saw a couple of guys actually carrying their bikes, in order to avoid touching their precious tires to the dirt road.
I did not then, nor do I now, understand just what their problem was.