With the knowledge we now have about the level and expertise of the NSA / CIA et al to access most so-called "secure drop boxes", why would any sane person use such a "drop box"?
Unless you believe the ongoing Snowden revelations are part of an elaborate false flag operation, there are still precautions that can be taken to get the information out.
The question is, does selling secrets via bitcoin make us more secure or less secure, as opposed to giving those secrets away, especially through a selected group of trusted journalists, like Bart Gellman, Laura Poitras, etc? You let the journalists make decisions regarding whether information therein put anyone's life in danger, and you build in redundancy by using more than one journalist at more than one news organization.
You've gotta admit, the system Snowden and Poitras et al designed to get that information public was pretty elegant. Especially in an age of ubiquitous surveillance and endangerment to whistleblowers.
As I said, if you're responsibly leaking stolen secrets, you're a hero. If you're selling stolen information, you're a scumbag. The profit motive makes all the difference in the world, and completely poisons the well when it's the whistleblower making the profit.