This is actually a pretty smart setup if you want to hide the entrance to your secret lab.
By making a door look absurdly evil with enough signs and ordinances telling people to keep out, you are garrunteed to have adventurers in there before you can even lock the door. This is the door that leads into your horrific death chamber of pointy death and doom.
Meanwhile nobody will really pay attention to the laundry room. I mean, what loot are you going to find there? His socks?