I'm not sure if you're joking

Just completing the pattern on one of Robin's throwaway theories about why people object to people carrying weapons when quite obviously people can already kill each other with their hands and maybe the furniture if they really want to. It upsets the status quo.

Unpack, please?

Sure.

the body's natural pheromones, for example, are an ordinary part of everyday human interaction, but date-rape drugs are rightly considered beyond the pale.

Humans are ridiculously easy to hack. See the AI box experiment, see Cialdini's 'Influence' and see the way humans are so predictably influenced in the mating dance. We don't object to people influencing us with pheremones. Don't complain when people work out at the gym before interacting with us, something that produces rather profound changes in perception (try it!). When it comes to influence of the kind that will facilitate mating most of these things are actually encouraged. People like being seduced.

But these vulnerabilities are exquisitely calibrated to be exploitable by a certain type of person and a certain kind of hard to fake behaviours. Anything that changes the game to even the playing field will be perceived as a huge violation. In the case date rape drugs, of course, it is a huge violation. But it is clear that our objection to the influence represented by date rape drugs is not objection to the influence itself, but to the details of what kind of influence, how it is done and by whom.

As Pavitra said, there is not a clear dividing line here.

We can't let people we don't like gain the ability to mate with people we like!