Ideologically, makes it easy to immediately search for any new games (either separate from or in addition to other added search criteria) that have been listed but do not have a single player slotted. Hypothetically if a DM adds a player, but then later removes the lone player, the flag would get re-applied again. This would make it much easier/quicker/more efficient to find games that haven't started yet and have a chance to jump on them before they fill up. Alternatively, make a checkbox and associated flag for listings posted at least within the last 7 days with the flag expiring after the total 168 hours.