To me it looks like SM only shows one of each kind. So most likely it doesn't create a list but overwrites anything found with the latest find (if read all goes from new to old) or just takes the first one and fails on the next ones (if read one goes from old to new).
It never used to on a read all, there was a huge list to scroll through, but yes these may be the earliest events of each type I have recorded so its behaviour has changed fairly recently if that's the case.