Diver Dennis
Contributor
sure. you see stacked rocks used many places to mark trails when there's nothing else to use, like above treeline where there's no trees to put a paint blaze on. Called "cairns" around here and I'm sure the scouts hiking in those areas learn about them.
But if you can see 20 in all directions from where you're standing, certainly don't serve the purpose of marking a trail, unless you want to get everyone lost!
Sometimes they marked the direction a family or group was traveling if there is no trail or at least a discernible one, especially if a second group was following weeks later.