I don't want to start a debate about the value of medical marijuana, but you do need to consider the motivation of the people giving you recommendations.
For example, chiropractors often offer free assessments which usually entail an X-ray. I'm not sure how risk-free this is, especially for healthy people in their early twenties. Of course, these assessments usually find misaligned vertebrae and lead the person to go back for a paid visit. Sometimes it's hard to compete with a certified practitioner's recommendation...
So yeah, completely different than a chiropractor or psychiatrist who profits from your ongoing treatment.
The CannaMed doctor doesn't stand to make more money off of you. But he stands to build a reputation as one who hands out the Rx.
People seeking cards aren't going to visit a prescriber who is notoriously stingy.
AFAIK Medical marijuana doctors don't have any financial interest in prescribing treatment. They get paid when you come in (which is only the one time), and if they think you can benefit from medical marijuana, they give you the card. They aren't getting paid every time you get high.
The stupid thing about that sentence in the article is that BIG SURPRISE, the CannaMed doctor recommended medical marijuana. No shit! That is why people go to them!