I can tell you that medical professionals wear scrubs or uniforms for several reasons. One of the main reasons is to maintain a clean and hygienic environment in healthcare settings. Scrubs are designed to protect both the healthcare professional and the patient from the spread of germs and bacteria. They are made of unique fabrics that are easier to clean and can withstand repeated washing, which is important in a setting where cleanliness is a top priority.
Another reason is to provide a clear visual cue to patients and colleagues that the person wearing the scrubs is a medical professional, and it can help to distinguish them from other staff members who might not work directly with patients.
While pockets are certainly a practical feature of scrubs, they are not the only reason why medical professionals wear them. Ultimately, wearing scrubs or uniforms is an important part of maintaining a safe and hygienic healthcare environment.
While in medical school and residency we would wear scrubs in the operating room. It’s a sterile environment and everything most be clean to prevent infection.
But the reasons I am aware of as to why you do are:
1) They don't want you bringing in pollens/dirt/etc from outside. When I worked in the OR, we'd show up in street clothes. Then we'd go into the locker room, and they would issue clean scrubs for us to wear all day. When we were done for they day, we'd change and return the dirty ones.
2) Things happen in hospitals. Scrubs are relatively cheap. You don't want to get blood, vomit, or other things on your nice clothes. So you wear scrubs in case that happens, then wash them or just pitch them if they can't be cleaned.
3) Like many jobs, they are a kind of uniform that identify you. Very few non-hospital workers wear scrubs, so if you see someone in them, you have a pretty good idea they probably work there.
There are probably more reasons I'm not aware of, but this is what I recall.