In the case of numbered, certificated physical items, the company is at least going to the effort to place an individuality on each item. (Until recently such numbering was impossible digitally) But perhaps youve seen candy bars and chips flavours these days also marked “Limited Edition”?
It still however exists as a marketting mechanism to make the item appear as if its value will at least not depreciate.
It should also be noted that I did ask you about this whole thing first; I would take your expert view on it regarding if items were issued on the promise of not being reissued, and if, as a collector, such a promise affected your interest and what you were willing to pay.
My theory is that any such promise did not affect your interest; you would have bought the item regardless of any perceived rarity status in the future is what I would guess if asked.