It does not have to be a club. Everybody who is serious enough to build a treasure with Bitcoin will always set aside a tiny portion of his regular income to buy Bitcoin. And not just Bitcoin, it could be divided among solid altcoins as well. The better club is HODL club. Not everyone who buys Bitcoin is committed enough to HODL them for a long time. Many are emotional owners. They cannot HODL when the times are bad. HODL club is made up of stronger Bitcoin supporters.
Sure, I don't mean a club where people need to sign up. More like a board where people display their commitment by telling the rest of the world that they're investing in the long-term.
I'm not sure about pure HODL. If everyone just hodls, what happens to actual adoption? People should be spending at least a portion of what they buy every month to foster adoption, even if it's as little as buying a Cryptokittie or playing some other blockchain game.