http://xa63tpfoaqt3zru2ehxjjfbpadwj4ha6qsdvtcqtyr3b7hmt4iaq.b32.i2p/usecases.html
By distributing your community across many different servers and networks, they lose their single point where they can monitor your activities.
Syndie also lets your community take whatever steps are necessary to
compartmentalize your organization, limiting the exposure from any individual
leaks - for instance, one group of users could use Syndie through a shared
wiki, while another group uses Syndie through a mailing list, a third group
uses Syndie through Freenet, and a fourth group...