I use the evac orders to try to get campers to move. When you have selected a squad, you can voice chat with them.
Find a favorite spot to drop ammo and you will get a lot of points and help the team keep supplied. I think the enemy can use you crate as well, so be aware of who will benefit.
What Dan said about dropping the crate on useless campers. Have never been able to kill an enemy with a crate -- not sure if you can.
I always drop rainbow skittles at F on Golmud. The Nancies who go there love them.