This is what I understand, though there may be differences in different places, depending on local custom:
A death notice is usually paid for, depending on the number of lines, in a special section of the newspaper.
I have seen instances where the death notice was only a line or two, referring the reader to the funeral homes' site, where more lengthy and detailed substance is provided, presumably included as part of the service provided by the funeral home.
An obituary is provided by the newspaper, without charge, as a news or editorial feature. It may be written by the deceased's family or by a newspaper employee. It may be on the front page or in a section near the death notices.
It may be that the family of the persons you were seeking chose not to have either or did not know the procedures for asking or filing for these. Or they could have been too bereft to pursue it.
In my own experience, the funeral home took the necessary information re relatives and arrangements and placed the death notices. I wrote the obituaries for several in my family and provided it to the newspaper, with my contact information attached. Apparently the newspaper checks with the funeral director (to make sure that the individual has indeed died), called me to verify the information and either printed it as given or rearranged or cut it to suit their space, etc. One asked my questions re the deceased and composed wording and headline that would not have been my choice - a little over the top- but that's the way it worked.
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