I did say 'rarely' - and honestly, was talking about RL. If someone is putting on a disguise to slip through a security checkpoint, attention is paid mostly to the face and clothing; not much to the ears. And what you're talking about are, well, permanent changes after all - which means that though they did it once, that alteration is probably going to be in their information, and thus they'll STILL have to alter the shape of their ears.