They may not have choice in the matter, at least not in what they can say publicly. Don't forget this is a legal case and they have liabilities and agreements to defend. This was a lawyers' statement to the court, a legal matter and one relating to national security.
a bunch of crap - everybody knows AT&T was/is helping the NSA
A bunch of crap happens in the courts today, our legal system demands it and depends on it. What you see is just lawyers doing and saying what lawyers do and say in such cases. I don't get agitated about it.
The crux of the issue, though, if "everybody knows" - what's the real point of the lawsuit, if not get the details of actual NSA intercepts, and the only reason there was a lawsuit to begin with was after "everybody knew" - a Catch-22. The lawsuit was completely political, liberal (not libertarian) in nature - it's just a way to get to NSA, which they cannot successfully sue, through a lawsuit against AT&T. Liberals made it a practice that anything they don't like politically, whether legislated, administrated or voted by the people, they will overturn in "friendly" courts, often in San Francisco (where EFF is based) or Massachusetts (where EFF was based before).
I must say I've been very disappointed with EFF in recent years, as much as I was very happy when they started originally. Their focus changed substantially from libertarian into a technology equivalent of ACLU (EFF refers to "Digital Civil Liberties"), and except few activities, mainly related to DRM/DMCA and RIAA, I haven't seen much good coming from them.
http://en.wikipedia.org/wiki/Electronic_Frontier_Foundation
Even more liberal is the splitter group CDT -- staffed with lawyers from ACLU and Democrat Senators and campaigns.
http://en.wikipedia.org/wiki/Center_for_Democracy_and_Technology