That will depend on the drug. If you're talking about heroin or crack addicts who've to essentially approach random people they don't know, then yes there is ob

That will depend on the drug. If you're talking about heroin or crack addicts who've to essentially approach random people they don't know, then yes there is obviously risk associated with it. However when you're talking about recreational / party drugs like marijuana, MDMA, etc., these come through large distribution networks with an inherent level of trust and common cause to minimize risk inbuilt. If you, for example, wanted to get some marijuana, you'd probably go to a friend that you know smokes it, because he clearly has a source for it. You'll go to someone you feel you can place some level of trust and confidence in, and likewise they will go to, or direct you toward, someone they place a level of trust and confidence in. Every actor in that scenario is seeking to minimize their risk. The consumer will use caution in who they deal with and likewise the middlemen or distributors will use caution in who they deal with. This will be underlined by the fact that low level recreational drugs dealing isn't a massively profitable activity. Only further up the distribution chain, far away from the end user, will profit rise and with it, risk. I personally cannot fathom buying drugs from someone totally unconnected online. The odds of you ending up buying drugs from a police officer when you go to a friend of a friend, versus when you're buying them from a faceless entity online are incredibly different.