This case deals with minimum wage laws and sex discrimination, much like Adkins v. Children's Hospital[?] 261 US 525 1923 and Muller v. Oregon 208 US 412 1908.
See also:
... together, 9.9% have a female householder with no husband present, and 16.2% are non-families. 12.0% of all households are made up of individuals and 3.4% have someone ...