I wouldn't say the ONLY people. This could be the next 'IQ test' where it seems the near opposite, the lesser intelligent ones are who are obsessed with them.
Going by magazines, common forwards and so on it seems the average man loves a good self-quiz.
But to remove some of the bias, we'd need approximately equal numbers of above and below average people to be going to the trouble of answering the quiz.
And in the back of my mind, I thought that the bulk of quiz magazines were sold to women, no? (Though I'm probably being too pedantic...)
Going by magazines, common forwards and so on it seems the average man loves a good self-quiz.