Lavabit was already lost, by shutting down it was lost the best way it could be. Groklaw, eh. It would be admirable to shoulder whatever risks they face, assuming everyone involved was aware, but I don't think anyone can be blamed for not being willing to.
From the NSA's statements, they look at people who have communicated with people with people they are investigating, or people who communicated with people who communicated with people they or investigating, or ... up to some number of hops away, with the nominal constraint that the person they're investigating be outside of the US. Many people communicate with Pamela Jones. If someone she exchanges emails with attracts the attention of the NSA, she exposes everyone she communicates with to the attention of the NSA.