This sounds like an interesting idea. But I have a hard time imagining myself completely taking 2 weeks off to go to an adult summer camp. Like, just a week is kind of a big commitment for any adult - but especially so if you have kids. And as someone who doesnt have kids - if I'm going to uncommit myself from my life for 2 weeks, I could go backpacking in the Himalaya or hang on the beach in Thailand instead.
While I'm not a fan of Theil, his event had appeal because of the people you would expect to be there - the rich and powerful and megalomaniacal. It makes sense for people within a common community with common interests to gather and spend time together like this, building relationships with people they care about and meeting new people in their community.
And that would be my big hesitation to going. The biggest draw to the idea is disconnecting from the your normal life and reconnecting with those who share the same values as you. But then, that sort of thing already exists. It's called Burning Man. Or Comic Con. Or Bonnaroo. Or the Highland Games Championship.
I'm a rock climber. I know quite a few places where you can post up for months at a time and live cheap with other climbers and just go climbing every day (to the point where we've deemed one of our favorite spots "adult summer camp").
I'm also a backpacker. If I want to, I can head to a popular long trail and start walking, and every night for weeks or months share a camp with others passionate about walking a long ways out in nature.
Or if you care about cultivating local community, you can go to a city street festival, or attend art classes at a community center.
So clearly, there are a lot of other options to choose from. And the big question on my mind is - what kind of people would this attract? After all, if you like canoing, you can just buy a canoe and go down a river for weeks with your friends. If you like shooting guns, you can buy a gun and drive to the middle of no where and shoot until you run out of ammo. So I can't help but think that the sort of people this would attract would be the people who just want to be at summer camp. They don't want to canoe or shoot, they just want to relive the summer camp experience. They want to relive the summer camp experience so bad that they are willing to take 2 weeks off and shell out oodles of money for it. Which makes me think that it would attract a crowd that has some kind of especially strong desire to regress into childhood, hashed with a general desire to not plan or make descisions - ie, the all inclusive resort/cruise/big bus tourism crowd