Restrictive commercial zoning limits competition for a space, enabling businesses that could not otherwise afford to be there. It’s a way for a community to inject some central planning and override the market when they disagree with its wisdom, e.g to kill the local independent coffee shop in favor of Blue Bottle.

It’s also a way to concentrate traffic where there’s infrastructure to support it, and limit it where there isn’t.

Proponents would say that that a good central plan adds value more value to the city as a whole than it costs in local inefficiencies.