The goal of membership sites are many and various. Whilst the majority tend to be related to Website marketing, account sites are beginning to broaden. In recent years I have seen websites that are related to cooking, self improvement and other issues that are of interest to a broader market. It's just common sense that this new development to decide on non-internet marketers will keep on. Once the membership world generally is your oyster why participate in a reasonably saturated industry like Online marketing?
More and more people are finding that creating and managing a membership site is not the task they could have thought it'd be. Granted, it does get some work, analysis and research, but there are very few firms that do not need at-least some work on your own part.