I suspect that one significant(not necessarily sufficient; but significant) difference is that cigarette smokers are typically nicotine addicts rather than cigarette addicts; so you don’t actually have to stand between an addict and their fix if you just want to clean up the delivery mechanism that’s most dangerous and most noxious for everyone unlucky enough to be nearby.
Expecting to beat the black market if that is the only option for nicotine is…naive at best; but making cigarettes sufficiently risky and annoying to get ahold of that people choose a path of less resistance is potentially much more viable.
