Users with None subscriptions in user's roster

Have checked some users’ rosters (Admin Console - User Options \ Roster) and i see entries with users which were removed from shared groups but accounts are still in the system. Their are shown with None none subscriptions. Are these entries creating any overhead? Maybe those should be cleaned up automatically?

Openfire 3.4.5

I noticed the same over here! Sorry, but i do not have a lotion.

Openfire 3.5.0