Countless black markets and closed societies existed in the galaxy. Some opened their doors to anyone that entered. The physical black markets at the Harkensen and Mancroft star systems served as iconic examples in the Komodo Star Sector.
Their barrier for entry was so low that practically any random seven-year old could jump over the fence. To call them black markets besmirched the reputation of all other black markets.
"They're more like the light version of black markets."
Due to their open nature and wide reach, a lot of paupers and poorly-connected power players tended to frequent these markets. This meant that while there would be a lot of customers for sellers to rip off, they weren't all that well-moneyed.