The message here is "life isn't a spectator sport" and I'm glad to see that message take hold regardless of its origin.
So, I don't do church very often, but I have participated in Occupy Austin's Interfaith group on occasion, and I've learned quite a bit about some faiths I was ignorant of. Churches have played a pretty big role in Occupy from the beginning, and a few of the most active participants in OA are also very active in their church. So, one could argue that the kind of people who seek out this sort of volunteer work in churches are also the kind who seek it out in secular forms, like Occupy. OA does a lot of the same things that churches do in our area: Feed and clothe the homeless (about half of our active occupation is folks without housing, and it's empowering for them to be able to help others, even as they themselves sometimes need help), offer community and support in times of need, and try to teach and share and demonstrate values that create a sustainable, healthy, equitable community (all without the use of force or violence or intimidation).
I'm not sure if your point is that Occupy is unneeded because churches already fill that role for some people, or if it is that it's surprising that folks at HN (who are predominantly non-believers) would be involved in something "church-like", or if you're simply pointing out the similarity.
If the latter, I'll add a point that might interest you, and further confirms your argument:
The consensus process that is used for making decisions within most Occupations is modeled after the process found in the Society of Friends (Quaker) church, with a few changes to handle larger groups and a wider diversity of views. Many of our facilitators studied the Quaker church process, and a few went to visit a Quaker church to discuss it and learn how the process works, and one of our facilitation trainers was trained in the Quaker church. Because of all this, I did quite a bit of reading about the Quakers, and found that I'm basically Quaker...without the belief in a god. It's a pretty interesting faith, and I'm glad Occupy gave me a reason to learn more about it.
I was pointing out that our community changes because "we", and by that I mean the people living in the community, go outside and change it. Spectating, and commenting loudly about how screwed up things are never changes anything.
I think it is wonderful that the Occupy efforts are helping to teach people this very important truth. This teaching, which has nothing to do with gods or mythology, is something that has gotten lost with people who have never been part of a Church community service group. I literally brought tears to my eyes to see folks in the New Jersey shore suddenly get this bomb this goes off in their head that there is no "government" or "them" who know what you need and how to fix it, there is just "us." And suddenly they become catalysts for huge groups of people who want to help but don't know what needs helping with. The CBS news story of the sisters who lived there dispatching volunteers with tasks because they knew the people, they had found out the things needed doing, and provided just enough guidance to let people do what they wanted to do, help.
I've found you can tell people that but they don't always believe it, they will say "Oh right, if I go out and start painting this three mile long sound-wall which is a blight because its covered in graffiti like anyone is going to help with that." And then they start painting and people just show up and start painting with them. It is easier for folks who believe in God because they just assume God will help them out, its much harder for folks who don't have faith. Occupy lets people experience for themselves the raw power of community action. That is a good thing.