A very easy way to use Bitcoin and create a black market, is to pay with Bitcoin and accept Bitcoin on all the things you sell second hand or used.
Discussion
The very nature of communications with error correction makes digital vulnerable to exposure, circumstantial perhaps but when did that last stop them...
And in addition to the already available resources out there, I've been curating a site of merchants that accept BTC.
That’s a way… sad that many people from the Hacker community are against Bitcoin.