According to conflict theories, who benefits from family structures where women stay home and men work for pay?

The men and probably the employer.

Explanation:

The conflict theory is a theory explaining that the society is an arena of inequality, because there is competition on the limited resources.

In this case, conflict theory simply looks at how new patterns benefit for a set of people while hurting others.

The benefit here is that, the women stay at home, while the men work, and this cause benefit to the employer.