Parades and line ups most likely go hand in hand. Whilst one has to do with the military, the other is totally linked to sports and processes some organisations and institutions use to call people together. Line ups naturally is no big deal, it entails making one's self available and responding to the assertion; are you here or not. Perhaps we sometimes put it in a different context, where we get to the base of a building during emergencies and call for the presence of everyone to ensure safety.

We do line up too for services such as the purchase of one product or another and especially during periods of high demand. Also...