I've seen vuvezellas (sp?) at a U9 AYSO Spring game before.
I've heard someone pounding a drum at a tournament game at silverlakes last summer at 8 am.
I've heard people sitting in a parking lot behind the fields at Vegas cup having a tailgate party, chugging beers and screaming at a kids game.
I was at a sand soccer tournament this past weekend where a group of parent sat behind the goal heckling the keeper every time a shot came at her. (Come on miss it!!! . Shoot it harder next time, shes scared).
A cowbell wouldn't be out of the ordinary.