The traditional nativity scene has the shepards arriving and presenting Mary and Joseph with a sheep the assumption being that not being rich like the Wise Men that was all they had to offer. Had this occured in modern times there would be 24 hour supermarkets stocked with cheap Chinese imports to ensure that at any hour you could find a relevant gift for any event. Had this occured this Christmas then it would be subject to weather disruption and lorries and what hours the stores were open for over the holiday season.
It reminds me of the old Steve Wright gag where a guy goes to the 24 hour grocery and finds the guy locking the front door. 'I thought you were open 24 hours' he said. 'Yes, but not in a row'.