Do climbers ever remove their harness when they are sleeping on the side of cliffs or for going to the bathroom? I imagine I would want to keep my harness on and be roped into the anchor even if the suspended bivouac has been set up and I am safely nestled inside of it.
Big wall climbers always leave their harnesses on, at most they will loosen or unstrap their leg loops while they're in their portaledge. There's really no reason to ever take off your waistbelt, as you can change your pants and shirt with it on (although maybe slightly loosened) and when you toilet you only need to take your leg loops off so you can pull your pants down to poop into a bag with detergent in it and store it in your poop tube/waste case. Climbers will pee over the edge (depending on what the etiquette is for the area), but only girls need to remover their leg loops to accomplish that (unless they're packing a funnel like a GoGirl or Freshette).