They only appeared idley in the waking sand, during cutscenes and instanced fights. They made it so that the warrior of light wasn't alone (because we'd all be dead without those companions if memory serves right).
Companions never had the Echo either (again, if memory serves) so they could be just a random npc anywhere in the world. It'd just be nice to set them to rest of they're dead, or reunion if they're not.
Like the Orphans christmas event :') I cried irl, seeing he was alright, alive and well.
