If the author puts it in the story, it's in there for a reason. It's all about the small details. Whether or not it's used immediately or hundreds of chapters later, it is up to the author.  Doesn't matter if the story is simple or complex, whether the author removed any extraneous details or that there's too many of them, the percentage of Chekhov's guns are high.

It's one of the many ways I know the author has put a lot of thought into the story.

Series that aren't on this list due to not being on Novel Updates: Sylver Seeker (Scribble Hub, Royal Road), One Piece (anime/manga)

Based on what I've read so far. Not necessarily in any order.