3v3 and up has always been based on the reliance of heavy artillery since more often that not; the spacing of the map means players are going to be blob pushing their units 50% or more of the time.
Your support gun automatically moving the gun around to get its arc on a target; instead of manually having to do so.
You know the MG arc? Pack howies and leigs have it but the autofacing was removed so they couldn't automatically move them around to shoot at targets. It's coming back in the dec patch.
wehr schreck require you to purchase a relatively expensive anti-infantry unit and then spend more munition to dump the unit's anti-infantry strength for anti-tank capability.
In short, panzergrenadier schreck are really expensive.
That, and faust with pak walls is just much better to kill tanks with.
You can't really spam PG with shrecks unless you want to engage troll mode; with OKW, it's just the way of life.