Were they strangers and weren't sure how to act? Did they not see any friends and neighbors? Maybe.
Usually, there's a lot of chatter, with people greeting each other.
There could be another reason. Maybe, just maybe, they recognized the presence of Jesus in the Tabernacle. Do you think?
The quiet atmosphere just reminded me of walking into a sleeping baby's room.
Look. Look, the Baby Jesus has come. Merry Christmas.