>>irgendwelche Assoziationen (gleich welcher Natur) über die Person auslöst
Normally I would only expect née in a marriage or death announcement, that is, in social rather than business contexts. Or in genealogy.
But since that doesn't seem to be the case here, if these senders are by any chance women who work in academia,* part of the explanation might be that they have published some things under their maiden name, then other things under their married name.
I too would have guessed it might be mainly an interim strategy, only for a year or two after marriage, but on the other hand, everyone wants their entire publication record to be findable. That might help explain the business card, which is definitely the oddest part, as it doesn't seem very temporary. On the other hand, divorce is probably equally likely, and in that case I might expect something like 'formerly' in English as well.
You say it's relatively uncommon, which is what I would expect, so on the occasions when it does happen, I would guess there might be some relatively practical reason for it -- if not that, then some other reason they feel it's important to mention a former name.
*IIRC? If so, I wonder if you would have any thoughts on this question, which wasn't marked 'wissenschaftlich,' but is.related discussion: hauptberufliches Personal