Refusing to be put off by an abrasive welcome and remembering we are guests in their home.

Fred punches every button with the nurses and outreach doctors. He has a history of extreme abuse and unattractive survival skills. Rude and unappreciative and often seems to deliberately punch buttons. Borderline personality behavior. No please/thank you. A demand not a question. Always someone else's fault. The system is wrong no matter what.
Many healthcare professionals would discharge him from their work load as too difficult and abusive. And yet one day he asked "When is my doctor coming?" You could see the child's fear in his eyes. He is end-stage AIDS.

You don't have to like the patient but they have a right to access to care. You must make it possible for him to have access to care. Remember, there is usually no support from family or friends to take over. You can say "He can get out for his drugs so he can go to the pharmacy." But access to his drugs is just ensuring his basic survival and staving off withdrawal. Going to pharmacy each day to get prophynal and pain medications is not part of survival. It ignores the reality of addiction. He does not care enough about himself to get these medications.
So, again, what is your purpose? To teach him a lesson? Or to deliver care to a very end-stage HIV Client. CO4 less than 10, zero ADV, high viral load, unstable living. Our goal: as pain free and comfortable as possible at end of his life. Call it what you will, our aim is to reduce suffering so they are not as ill as previously. This may not match your viewpoint of your job. If it doesn't, you may be more comfortable in a more cordial part of the community.