I am surprised there are not more votes on this. There are so many reasons to have lists, not having them neatly in folders or categories means that there are duplicates upon duplicates of the same list.
Reasons for duplication: One person used "donor," another used "constituent"; a search result didn't find the list because one user included a unit separator Another reason this would be helpful: Users cannot delete or edit former users' lists!
This creates additional work for our advancement services team who could just go into a folder and use a list that is already created.