Then again, in fantasy worlds it is logical that keys are hidden in more original places than under the mat in front of the door.
Like, where did the Sharrans hide the key to the door of "the study" in Grymforge ? (The room where the Merregon and Hellbeasts are locked up)
Not under a doormat, but in the pocket of a corpse hung from the ceiling in front of the door. Now that does look like a proper Sharran storage place.
