The people who write the fire protection codes thought it was a good idea, because drywall gives you enough time to get out in a fire. Manufactured homes (i.e.

The people who write the fire protection codes thought it was a good idea, because drywall gives you enough time to get out in a fire. Manufactured homes (i.e. trailers) will have wallpaper integrated into the paper of the drywall so that the painting step can be skipped. Most people don't want this and would rather pay more to have a painted wall.