I am not going to have the popular opinion on this thread, but that might be because few of you have spent much time on the patient side of this.
Have you been hospitalized as an inpatient at a teaching facility?
Residents, fellows, and "students" with poor bedside manner tend to feel they have the right to come inspect you without even introducing themselves in great masses when you are unable to defend your rights (if you are pediatric, elderly, intubated, or otherwise unable to communicate well). HIPAA is supposed to let patients know who will receive their private health information--so clearly this is not a HIPAA violation if you are standing right there and the patient is disclosing information in front of you...but you may underestimate the feeling of subordination many people have to their physician. YOU are on track to being a doctor, it doesn't have the same sense of power or awe to you because it is attainable--for many people, that is an extreme position of authority and power, and they are in one of the most vulnerable positions of their life. They share things with their physician they may not even share with their spouse. SO, when that physician walks in the room and asks, "do you mind if ____ watches?" a large percentage of patients will not feel comfortable declining. THAT IS NOT OK. It is also not ok for patients to simply be told that a premedical student is a medical student and that they will be watching an exam, procedure or other medical event. Physicians who are doing that are violating their patients' trust. There are plenty of WILLING patients who will let you observe them VOLUNTARILY. If you shadow a physician and he/she does not introduce you to each/every individual and/or you do not ask permission to witness the private medical moments of each patient you see--shame on that doctor and shame on you. That is an important lesson you should be learning, and an important lesson you are missing.
Initiate your clinical exposure by doing something useful rather than simply "shadowing." Volunteer at a hospital or assist in a research project--become a useful element in these patients' lives rather than just a voyeur. I think the concept of shadowing fails to protect so many patients' rights.
I was an "interesting case" as a child--I had a one in fifty thousand defect. Everybody here would have thought it ok to "shadow" a physician to gawk at my unique ailment and progress...how many of you would have thought to ask me if it was ok?