Why wear a hospital gown?

Lots of reasons.

If you mean a doctor's gown... # To act as a layer of protection between you and bodily fluids. # To protect the patients from your leaving trace contamination from your street clothes. # To act as a form of identification that you're staff and not a patient. # Gowns are easily washed, hard to stain, stand up to the harshest laundering techniques, and don't cost much. # If you mean surgical gowns or sterile gowns, they're sterile and are part of the sterile field, this providing a boundary between the sterile field and the rest of the not-so-clean world. If you mean a patient's gown... # It gives you something to wear to prevent embarrassment, while still allowing hospital staff easy access in case of cleaning, examinations, etc. # It too is super-inexpensive and easily cleaned, so no worries if it gets dirty. # They're reasonably comfortable and hypoallergenic so you can sleep in them easily. They don't shed, so wounds don't become easily contaminated.