Sorry -- you are incorrect. There are some medical conditions (and medical treatments!) that can cause extreme BO, and the patient/employee is unable to control it. These people do not smell "fresh as a daisy," but they cannot be forced to leave a building, or even a particular room in the building, because of it.
I am a patients' rights advocate, and this is exactly the kind of thing I deal with on a regular basis.
It's too bad that people cannot be banned from a public place, or internet forum, for being ignorant and malicious. Sadly, I am all too aware that you cannot. UNTIL you cross the line, anyway.
I seem to have touched a nerve.
However, you HAVE hit on the key issue: the person with BO as a product of a real medical condition cannot control said odor (and is protected under the ADA). A person who merely does not bathe can, but chooses not to. A smoker can control his emissions of cigarette smoke. Enough refuse to do so that their emissions are controlled for them.