I think the best way to look at the facts that these cards are expensive, non-reusable, and spent like there's no tomorrow in combat is this one:
I am Heavy Weapons Guy. And this... [grips Sasha] is my weapon. She weighs 150 kilograms and fires $200 custom tooled cartridges at 10 000 rounds per minute. It costs $400 000 to fire this weapon... for twelve seconds.