Mark Zuckerberg REUTERS/Brian Snyder A bunch of liberal advocacy groups — including MoveOn.org, CREDO, Presente.org. Sierra Club, Democracy for America — have pulled their ads from Facebook in protest of the company's lobbying arm, FWD.us, which has also supported the building of a gas pipeline from Alaska to the lower 48 U.S.

The economic impact of the boycott will be negligible to Facebook.

But that's not the point.

It's the third recent set of unintended political consequences that Facebook has stumbled over since it launched FWD.us, its lobbying arm.

FWD is supposed to be a single-issue advocacy group dedicated to immigration reforms that would allow tech companies to bring in more smart, highly qualified foreign workers.

But in pursuit of that narrow goal, it has ended up supporting ads for Big Oil and the politicians who want drilling in the Alaska National Wildlife Refuge, and the Keystone XL pipeline to be built from Alaska to the Gulf of Mexico.

In protest, CREDO Mobile tried to take out ads on Facebook asking CEO Mark Zuckerberg to pull funding for those oil ads. But Facebook banned the CREDO ads — on the grounds that using Zuckerberg's face is against policy because it's confusing to users — and handed CREDO way more publicity than its ads ever would have gotten.

And now CREDO is back, with a bunch of fellow travelers, to highlight Facebook's uneasy political alliances.

"Ostensibly an organization dedicated to comprehensive immigration reform, ads run by FWD.us’s subsidiaries have also attacked health care reform, the 2009 stimulus, and 'Chicago-style politics,' CREDO said in a statement.

The boycott group also includes Progressives United, the League of Conservation Voters, and 350.org.