I don't think that attending a church is a requirement for being spiritual. Actually, I don't realy think it matters a whole lot what denomination or even religion you believe in. I think there is one god for eveyone and how we choose to relate to that entitiy has more to do with our experiences and perceptions than it does with the HP.
I do think that churches offer a community for people and in today's world that can have real value. I live in Iowa so by no means do I live in a big city. My city is big enough, though, so that for the most part my day to day interactions are with strangers. A church can provide a base community. A place to get centered and to find support. I have been able to appreciate that even more lately since my world has changed. I have left my congregation of 20 years and am finding my place in a new congregation. I still haven't figured out where I fit in.