I don't want no scrubs

Now, I have spent more than my fair share of time in the hospital in the last few years for various surgeries, consultations, etc. and I had it in my head that hospitals are a sterile place so that people do not get any sicker than they already are. Then why is it that as I walk to work every day, the nurses and doctors from St. Paul's hospital are wandering the streets and frequenting Starbucks wearing their scrubs with their stethoscopes still hanging around their necks? Perhaps this is part of the reason why we keep hearing stories about infections spreading in the hospitals...it is because of the cooties the staff are bringing in because they're too lazy to change into street clothes when stepping out for some java or a smoke!