That is true, for example, you cant necessarily edit the background of Spear Pillar without deleting the palette (unless you have Photoshop

Black and white usually prevent good modifications, same goes for Luigi's mansion or any other stages/backgrounds/ textures that have a specific palette, the only way is to delete the palette (which admittedly and some times causes weird things to happen) or go to Photoshop and use the "tint" option which will then allow you to rather treat it like a normal texture seeing as how its given color