Are the only healthcare professionals you know in psych wards? Dark humor and "dehumanize"-ing patients is standard coping for nurses, doctors, and basically anyone else who deals with the physically and mentally ill. That doesn't mean that they don't have empathy for them and understand that there's a fundamental disconnect between societal norms and their behavior.

The person I replied to posted a laundry list of complaints about when those damn homeless jerks made them uncomfortable after saying they are so hard to empathize with. It's so whiny and disconnected from the actual hardships that caused these people to behave this way. Why can't they just be clean and polite and normal?