All of the reasons mentioned in the thread are valid reasons I think, but the underlying reason right now is mostly the fact that there is giant disparities in the global drug market to begin with. The drug market is not flat at all. It's mountains and gulleys. Which makes for excellent arbitrage opportunities for intelligent sellers in the right place and time.It's not like selling pencils or coffee. A drug can cost 2-3x more between two different states in the U.S and this is not unusual.You'll notice there's a 'over-representation' of Australians, New Zealanders, Scandinavians here on the Silk Road. That's because in their countries, all the drugs on the Silk Road are practically half price in comparison to their streets.