It seems to me that not ALL of them were expected to die in combat.
They have different "classes" of clone, fit to different tasks.
You've got the cannon-fodder grunts, sure. And the damn good grunts, like Millia.
But you also have archivists like Exedol that were expected to live as walking knowledge repositories, and clearly aren't suited for combat roles.
And then there's commanders like Britai. They're "built" to a more durable standard(Britai himself said so after being spaced, and him and Bodolza both tower over the regular rank-and-file zentradi). Presumably because a highly-experienced commander is infinitely more useful than a fresh-from-the-test-tube commander.
Britai's plate implies this too. Assuming it was a patch-up after an injury, it means it was worth trying to save his life instead of just finishing the job and popping a new Britai out.
If it's an implant that offers him information beyond what he can see and hear, along the lines of the BDI system, it means command zentradi are harder to make, because the implant can't be grown like everything else.