Has any darknet marketplace tried focusing on a local area, such as San Francisco, and using something like geocaching for distribution? I feel like if the drugs were planted in an area before hand the dealer wouldn't have anything incriminating at their house, and they would just need list of gps coordinates. Additionally finding a random package of drugs seems like it has a good case for plausible deniability.
I'm sure that there are huge hurdles to come over with this idea, but it could offer some advantages over delivery and seems like such a strategy might work and may have already been tried.
I can't even imagine the media ruckus it would cause if this started occurring in local areas. An oobvious problem is for the buyer to get the package, but that may not be as big of problem as it sounds.
As someone who has geo cached before, it would be kind fun going on a hunt, finding said product, dosing, and trying to find your way back!