(V1s suck, unless they behave differently then vCoH ones, and I've never been impressed with firestorm)
then you don't know how to use them.
1) Defensive positions are very, very common in EIR. Garrisoned buildings can be nasty if you don't have nades/flames/mortars handy.
2) You can wipe out a LOT of shit if you are smart in your placement.
3) Even if you do drop it right on their heads (Which is a bad idea usually), it forces them off a position and wrecks defenses so you can rush up
4) Did I mention that they basically obsolete howitzers?