|I'd say you can consider Usagi Drop falling in this category. The volumes after the big time skip (basically half manga) are the "epilogue" of the story of him raising Rin. If you consider that the main reason of the story, all that part sounds like an (unnecessary imho) epilogue.
Maybe you can consider also Sword Art Online (novel) similar to what you asked, but it's more
Spoiler (mouse over to view)
there is another reason to go on, totally different from the previous one, rather than "everything is ended" even if literally speaking everything (=the SAO world) is ended.
But I mostly agree with FormX: if there is not reason to continue, why drag it?
What I like in Trivial Pursuit style. Pick your category: