I've just thought of another consequence: if the waste is always teleported out, then the muscles of the bladder and the rectum are gonna become dystrophic, while the anal sphincter forgets how to loosen. In addition, the urinary tract might dry out for want of any moisture from the bladder.

Now imagine that one day your trusty crap teleporter breaks down. You're stuck with piss and shit filling the bladder and the rectum, while both outlets are plugged from years of disuse and you don't know anymore how to push the stuff out.