In many cities (thinking of Toledo OH) you can snag free lots.

You can also snag a lot of cheap vacant units.

And nobody wants to change the zoning to allow 3d printed shanty towns.

Developers would love to print disposable housing that needs to be abandoned and rebuilt every 20 years or so. The trick is that they want to sell these things for a big markup. They don’t want to flip a $1000 unit at cost.