> Only as long as its use for the former doesn't outweigh its use for the latter.

That's just a self-fulfilling prophecy. Obviously the early adopters are going to be the people for whom the existing system fails, but if you use that as an excuse to ban it or otherwise make it an insurmountable inconvenience for ordinary use through regulatory suppression then you're just preventing people from using it to buy lunch, not preventing them from using it to buy drugs. Which is useless and spiteful, especially when you're not going to address any of the problems that caused people to want it to begin with.