I doubt most collectors would ever shoot a full original box of any old ammo, so what primers it has are a moot point. At the cost of collectible ammo and what it's worth once it's been fired I think it's something nice to have to go with a old rifle.
I picked up a late 1800's box of .40-63 Ballard Everlasting ammo with paper patched bullets at the CGCA show in Colorado last May. I bought it simply because the price was fair, and I own 6 Ballard rifles chambered in this cartridge. I have plenty of new brass to shoot, but having an original box of paper patched ammo I felt was neat to own.