Nope. While this is popular lore on many college campuses, the truth is “brothel laws” don’t exist.
Some communities do have zoning regulations that prohibit more than a certain number of unrelated people from sharing a residence, but they have nothing to do with brothels, which are identified by their function, not by the number of people residing within. Furthermore, student housing such as fraternity and sorority houses are generally exempt from such restrictions.
So, why do so many colleges lack sorority houses? It varies from campus to campus, but generally the reasons stem from financial constraints, the lack of suitable houses near campus or (oddly enough) the erroneous belief among sorority members that such a law actually exists.