Alcoholism is an addiction and deserves a great deal of help and assistance.
Not quite. It is a type of addictive disease. A disease is not something that can be turned on or off. You might as well say, "I understand you have cancer, but don't you dare bring it to work with you".
Showing up for work intoxicated cannot be tolerated but any approach that ignores the medical facts of addictive disease is an approach that only treats the "convenient" symptoms.