Because it's ok that incendiary strike, phosphor artillery or any other allied artillery can wipe the units in your base, but axis zeroing artillery is not allowed to do that and got ninja nerfed or bugged so it became completely useless. Can't give okw a counter for the b4 one click win artillery.
I am very disappointed with zeroing artillery. 300 munitions for 1-3 weak artillery shots? Where is this "ramping up the longer the enemy is in the sector". For 300 munitions I expect this ability to mean "get out or die" but this is not the case at all.
The walking stuka was sweet though. You don't see it get to vet 4 very often and start launching those fire rockets.