Over time, planners did exactly that: Zoning and building codes required homes to be built with ever more features and amenities. Minimum parking requirements were added and maximum residency limits appeared. Some of this was done to upgrade housing stock or protect health and safety. Some of it was done to eliminate entire forms of housing that gave the poor or the unlucky a continued toehold in richer neighborhoods. Does it really “protect the roomers” to move them from a boarding home without parking spaces to a tent beneath the overpass?