I grew up in a small-ish town and when there was a construction site there was inevitably a large pile of dirt somewhere nearby. Often 10 or more feet tall. If construction wasn't occurring it would be occupied by neighborhood kids digging, building dirt bike tracks and most importantly building walls / battlements.

Various neighborhood kids would take the dirt fort and try to hold it against the other neighborhood kids who came and ... everyone threw "dirt clods" at each other. A few rules like "no rocks" were understood.

Otherwise the battle resumed every day the workers weren't working on the dirt pile... it was glorious. Win or lose you returned home each day dirty as could be, and very happy you did your duty that day alongside your friends from the neighborhood.

That is a long way of saying that sometimes I see some strange "tribal" stuff that seems weird to me, and actually no I kinda get it.