Being a Mormon isn't a secret either, unless you are an outsider that wants to enter their sacred temples or know anything about the true inner-workings. And....not just my conspiracy theories, but the word of my Mormon friend, who actually just got back from visiting the Temple in Utah.
In other words, just because it is known, and even advertised, that some people are Free Masons does not therefore imply that a certain part of the Mason's inner-workings, rituals, etc are not super-secret. Duhhhh..
I also know that the U.S Government exists....and a bunch of other governments, too...and, shock of shocks, they all have super-secret inner-workings that I don't know anything about.
So any fool that thinks you have to be a conspiracy theorist to believe that the Free Mason are a super-secret society is just naive.
Whew...
THAT being said....in order to become a Mason, you must first eat the beating heart of a new born lamb and sell your soul to the Devil.