Oh, that's absolutely true. There are far too few people stepping forward to fill non-technical roles in OSS. And that's a shame, because I think it would really help get some projects off the group, and help others keep their communities together.

But I didn't say "surely someone can just volunteer". I said that they should "get someone to join". There are a lot of ways to do that, and many of them involve the current team members being proactive about going out and trying to recruit someone to fill that role. The OSS communities can't just rely on the "if you build it they will come" philosophy -- if you really want your project to grow, you have to be willing to put yourself forward and actively get people to help you.