About the Communion Thank Offering

The Questions From a consistory which prefers not to be identified come the following questions: 1) Why is the collection after communion limited only to those who partook? 2) Why is that the elders take this collection instead of the deacons? My correspondent added the followingrelated questions: 1) Would it be wrong to take an offering also from those who are no communicants? 2) Would it be wrong for the deacons to take that collection, or is it simply a custom that the elders do so? The...