we can take this thought experiment: a vendor on SR has invented a totally impenetrable bag solution, impermeathon. Unfortunately, the only way you can get impermeathon is by ordering it from them. Even if we all agree that impermeathon is impermeable , and dogs will not hit on customers packs if the drugs are in the impermeathon bags, it is even worse than using no sealing bag at all now because all the vendors are centralized in getting orders of impermeathon from a potentially rouge and certainly compromisable node. At the end of the day the argument has nothing to do with what materials are best, and everything to do with what vending practices are best. Given the choice between perfect packaging and overall vendor security, we would be wise to opt for overall vendor security. Thankfully there are ways you can get impermeathon without going through channels on SR, but just keep in mind that if the vendor is compromised it doesn't matter if they ship their drugs through a teleportation device that bypasses customs and postal system entirely.