It was common before the 20th century for heterosexual men to sleep in the same bed. People were poorer then; beds cost a lot of money and were hard to transport; and, most important, bedrooms were COLD in the winter and one could risk freezing to death were it not for a bed companion.
Even putting guests who were total strangers in the same bed for the night was common. In colonial times, the practice was called "bundling." IIRC, even guests of the wealthy George Washington at Mt. Vernon were "bundled" in the winter.