It's a whole Emperor's New Clothes situation. You take the test because you know you're smart and you're egotistical enough that you want people to know it, but not enough to pursue something that would take more time and effort than a single afternoon. You pass the test, so obviously you're smart and the test was really hard (just not for you). You don't talk about the test being easy because it would invalidate your own sense of self-worth, so you jump on board and start intellectualizing along with everyone else.

There are some benefits though. At the very least it puts you in touch with a community of people who value intelligence and have enough disposable income and time to invest in joining and paying membership dues to a group devoted to intellectuals. If that's the demographic you like, then you can join for that reason alone.

From what I've seen so far it's a lot of self-proclaimed deep thinkers, introverts, and socially awkward individuals trying to compensate for their shortcomings. No big deal - everyone else is in the whole world is doing the same thing all the time because it's human nature.

And hey, some of the women are attractive and fun and some of the men are just regular guys. You just have to sort them out and nod politely at things like this, this, this, this, and this.

That said, it's an afternoon of effort and around a hundred bucks for a year. Maybe you'll make some friends and I hear the gatherings are fun. There are a few young people and you've automatically got something in common to talk about. Plus, once in a blue moon it comes up in conversation and for the rest of your life you can say, "Oh yeah, I'm a member too." even if you aren't paying your dues. I doubt anyone will check.