My understanding from reading the article is that is was a stray, of sorts. It says the people moved into the house and there was a cat living outside and they "adopted it."
''Fluffy reportedly had been living outside the house when new owners moved in within the last couple of years and adopted her''.
It sounds like it was a barn cat of sorts, not a house cat. It's not like they "got" a cat and started leaving it outdoors. It was an outdoor cat that came with their house. Probably left there by the previous owners or a stray that the previous owners "adopted" as well.
In any case, I am glad the cat is okay. I got a laugh out of it growling at the vets when they revived it. There is gratitude for you.