alt Hacker NewsUp to a point. Yes, it is nice to mix housing and retail and the like, and some zoning laws prevent this. But you have to look back into the 19th century before zoning laws existed and you had things like slaughterhouses opening in residential neighborhoods. Zoning has good reasons to exist.
Residential and commercial can work pretty well together, up to the point of noise and chemical risks. Industrial will pretty much always need to be zoned because of different hazards it presents.