Is there a good reason why they shouldn't? I think anything that stacks should stack to 1000. I would be interested to see the counter argument.
I frankly can't think of any item that occupies more than one slot in my bank/inventory. Unless it is a TS item and I got more than 1000 of it.
Stat food would be nice to stack more than just 20 Raxil fish or whatever. But I am still waiting for the bigger spell book.
*shakes fist* I remember when bags could not be placed in other bags. You damn kids and your fancy rules.