The gullible are already getting snake-oil in the form of herbal remedies and homeopathy.
Ben Goldacre's book Bad Pharma details the serious personal and social costs that come with poor drug trials. Everyone urging the abandonment of caution here seems to assume this new drug already works or, at the very least, the effects of its usage could not be worse than the grim prognosis patients already confront. But that's what proper trials are meant to establish. Snake oil can come in pill form, too. And even with the current precautions, we've ended up with a number of ineffective, expensive, and sometimes deadly drugs on the market.
As with the drug war, we drive people into being basically criminals when they're in reality suffering from a medical condition.
So rather than being allowed to experiment with extremely desperate volunteers who could likely one day provide some real EUREKA therapies, we send those folks to the dark side where they're much more likely to spend a great deal of money and be taken advantage of.
That's a huge practical loss, but an even greater ethical loss. At its very core, we are throwing away people's right to choose what to do with their own bodies. Being okay with that ethical tragedy is like being okay with rape or torture for some poorly proven "greater good".