If they only killed themselves, I'd be enough of a callous prick to agree. Addicts to anything, Budweiser included, destroy their families, and pretty much wreck the lives of people all around them.
I don't disagree in the slightest. However, it is a severe error of logic (not to mention ignorance of history) to propose a prohibition as a solution to that problem. As you note, alcoholics can inflict just as much pain on those around them as can heroin addicts - yet we do NOT arrest massive numbers of alcoholics, except where they commit other crimes as well. We did, once; it proved to be a total failure with consequences worse than the behavior that spurred the policy; and we would be fools to ignore that experience in similar cases.
You'd like to kill anyone or anything that anyone could enjoy, probably including sex unless it was to produce offspring. I rather think you would enjoy killing. Murder, Inc.?
You're very bright. < /sarcasm >