You are replying to a flame ht 90 ammo then this topic is about 50 ammo vehicle mine and then you are adding a 100 ammo shrecks. Most here talking the effect of t70 and flame ht early game before first medium tanks start rolling to the field.
Yes you can get shrecks with pgren, but you can forget flame HT then or you can put tellers. It's always a choice with OST as it's so heavy in munitions use.
By the time T70 arrives, you can have both.
Just don't spam LMGs.
Ost doesn't have it any harder on muni front then brits, USF or even soviets nowadays(now that every single ability exvept for mine costs more and guards were always ammo hogs).
Yeah, you can't have it all in early game - no one except OKW can.
Point is, you DO have options for a follow up if the mine did 380 instead of 400. Even 222 can finish off T-70 like that.