That's wrong too though: if I get 1000 people who love professional cycling news to sign up to HN and start upvoting articles about Alberto Contador, that doesn't mean it's on topic.
It's wrong only if you assume that guidelines should pertain to an absurd range of deliberately destructive yet highly implausible scenarios, as opposed actual problems that could regularly occur in their absence.
My example is contrived, but if you think about things like the TSA, US electoral politics, and that sort of thing, it begins to look much more realistic.