In the original post he mentions that he purchased the containers specifically for the purpose of the donation, so it's likely that the containers sat full for years after being donated and were only incidentally re-used.

He also mentions that the person who originally accepted the donation was pushed out of the VCF organization, and did not have a say in the material being disposed of.

There is a possibility here that the containers sat for years after they were accepted, no one was left who knew why they contained a bunch of papers, and so they thought it wouldn't be a big problem if they disposed of the papers. Being a supposedly archival organization, however, if this was the case it would have been very poor judgememt.

I'm the kind of person who keeps random marketing materials from obscure gadgets from 40 years ago, so I can feel the pain of these documents having been lost.

That being said, once a donation is made, in general, is there an obligation to uphold any wishes of the donator? I guess there is, in many circumstances.