I think violence against women in the comics is related to violence against women in the movies. Many of the people who were working on the comics freely admitted they were influenced by the movies. And in the old movies, violence against women was common. Sometimes they acted as if it was acceptable. And sometimes they acted like it was funny.
"The Spirit"gave his girlfriend a black eye, too. I thought it was probably because of Carole Lombard, but I don't know if Will Eisner ever remarked on that business.