The bearded hive is simply more populated or may have less room to accept incoming nectar keeping field workers home.. Even this late in the season it may be a sign a hive is headed to swarming. We like to work those hives and look for high drone numbers, one of the earliest signs of swarming, and for active queen cups or cells. If found next would be some swarm management. Maybe you have a very prolific queen and just a good strong hive going into fall. Best to find out soon.