Why would an intelligent person join Mensa?

A study of intelligence and neurosis discovers that members of the high intelligence club, called MENSA,  are neurotic. Smart happy people don't join narcissistic organizations. In fact, it is kind of a stupid thing to do, unless you are smart and neurotic.

After comparing this with the statistical national average for each illness they found that those in the Mensa community had considerably higher rates of varying disorders. 
 While 10 per cent of the general population were diagnosed with anxiety disorder, that rose to 20 per cent among the Mensa community, according to the study which published in the Science Direct journal.