Yeah, just seemed odd to me to use freeze-dried cheese when a regular brick of unrefrigerated mozzarella will keep for weeks unopened and once opened, for several days.  If it stays open a week, you might need to cut off a bit from the outside but the inside is still perfectly fine.

I know, grating warm mozz is not the easiest thing to do but then again, it's not an insurmountable task, either.