The fact that a previous owner went to the trouble of "hiding" these records in what I assume to be a professionally bound album obviously speaks to his/her likely idealogical interests in the records, as we can all surmise.
However, aside from the binding, the 78s themselves are part of a historical record, and the medium was used to preserve all kinds of audio during that era when media formats were limited. The idea of a private citizen and or an archive wanting to own these records for historical purposes is not so far-fetched. I detest fascism as much as the next fella, but I also don't believe in erasing history. Such documents are valuable, if for no other reason than to provide a reminder of paths to avoid. That said, I wouldn't devote shelf space to these things either.