One of the quirks of old TV sitcoms are always the scenes in the bedroom for a married couple.  Shows like Dick Van Dyke and I Love Lucy had the couple separated with single beds. This had to do with the US Broadcast Standards and Practices of the day. 

I was surprised today watching The Danny Thomas Show that had a bedroom segment with Danny Thomas and his wife in the same big bed. I thought at first maybe the single beds were moved together, but no it was one bed with king or queen sized covers.  The show I watched was the same B&W era as Dick Van Dyke, but unlike the Petrie's, the William's were sleeping together.