I think there's a problem when we talk about drugs in such absolutes and say that people are either traffickers or victims. The traffickers plunder others, who become victims by using drugs. The fact is that most drug traffickers who get caught are in fact drug users. Once you start using, that's one of the ways you maintain your habit. It becomes a lot more complicated than just absolutes.
The fact is that four out of five people who went to court did not get a conditional sentence; they were sentenced to jail. That suggests to me that with drug offences, just as with every other criminal offence, you get far more of the low-level offences than the high-level offences. Higher-level offences are harder to investigate; there are not as many of them.
That one-in-five statistic doesn't strike me as surprising, particularly when you recognize that to actually deal with the addiction, 700 days in the community with access to treatment under intense supervision is more likely to bring about a better result than 47 days in jail in the kind of environment you described.
I think we have to not be so absolute about this.