Why do hospitals let doctors, orderlies and visitors slosh bacteria around with every footstep?

FORBES: Hospitals' Nightmare

As you sneak through each level in Mark of the Ninja, every footstep and every sound is illuminated by a sound ring.

FORBES: The Importance of Agency

How could I stay abreast of what was going on in my house if, when the snow came, my every footstep in the yard would leave a trail of incrimination and such clear proof of a prowler on the grounds as to get Diana on the phone to the town police?

NEWYORKER: Wakefield