I grew up in a large city in an area where Italians and the Mafia were present. When you talk about black markets Exactly what do you mean Because i have bought from stores where i'm sure it was black market due to the nature of the owners and never once felt unsafe.
We were in a poor area of this italian area and we as kids always were treated as Royalty when it came to the "Regulars" in the area...We were always given money and toys at christmas and always a thanksgiving turkey.
I think by "Black market" being dangerous you must be referring to some serious shit.
What you are describing is a real life black market. I actually think that is safer both for the vendor and the buyer. What I mean with "black markets" are websites where you can trade illicit goods.
Sites like Silk Road etc...
I don't think you will go to prison for ordering weed online but if you are a drug dealer looking to setup shop you won't be home free selling on these black markets on the internet.
Then it's "serious shit" since you are sending out illegal drugs in packages all over the world.
If it is a real black market, than it can't be considered safe as things that are presented are either illegal or don't have safety control (but sometimes it's just about avoiding paying taxs so in that regard they can be relatively safe) but overall, just know the risks and what you are doing
Of course a black market can never be safe since you are participating in illegal activity. But as I mentioned sites like Silk Road have been described by the media as McDonald's for illegal drugs etc.