Why is Nobody Building Mixed Use in a Mixed Use Zoning District?

[Robert C.]

Any theories?

I've been looking at building projects within Mixed Use zoning districts in my town. Surprisingly, it seems to me that nobody is taking the city up on Mixed Use zoning incentives. Developers are instead only building residential (either townhomes or apartments). By building mixed use, you get better FAR, smaller setbacks, and more height, so what am I missing? I would think it would be a no brainer.

I've thought of a couple reasons, but I thought I would see if anyone had some input first to see if our ideas sink up. Thoughts?