I'll just pick up on one piece of what you said, "meds from a psychologist." While I don't disagree that greed may be a part of it, unless that person's extra training involved a medical degree... that's truly been a crazy idea given the things that can go wrong even with "simple" medications, even when you know what questions to ask about other preexisting conditions and how to interpret the answers.

The other thing is that with the current system (i.e. medical doctor prescribes), there's liability coverage through the doc's liability insurance, which unless psychologists are interested in taking on huge liability insurance premiums...