Just the title. When a man works hard for his wife that is his choice. That does not give him the right to abuse and manipulate the women into doing whatever he desires.
The same should be for employers. Just because you pay someone for their time does not mean you can lay out the boundaries for what is and isn't ok. You can't turn around 12 months later with a new contract and say “but you have a choice, you can leave any time you like”.
I guess thats the one difference, society thinks we have a choice in this matter.
note: wifebeating can be exclusively verbal.