That trip home may have been the longest trip that car had taken in a while, with a partially clogged oil pick-up and bearing material starting to give in addition to sludge and whatever else, it may have been the straw that broke the camels back. If the previous owner drove it very rarely or not very far he may in fact not have know about the problem....just my .02 cents. I always remember there are 3 sides to a story, mine, theirs and the truth