Just like "Mensa" is better than "people more intelligent than you", or "Toastmasters" is better than "people who can speak better than you", also "LessWrongians" is better than "people who are more rational than you".

It's easy to start seeing "LessWrong" as an arbitrary label if you're used to the name, but it totally does have a confrontational meaning in the way that "Mensa" and "Toastmasters" don't and in the way that "more rational than you" does.