Mark Thompson says they were:
The concept started out as a relatively small idea organized by a handful of libertarian activists. Movement conservatives saw an opportunity to co-opt it - and they did.
To them, the Tea Parties aren’t just an outlet for expressing frustration over the recent orgy of government spending, they are an opportunity to complain about gay marriage, affirmative action programs in government hiring policies, and just about everything else that movement conservatives oppose even more vehemently now that they’ve been beaten - badly - in consecutive national elections. Never mind that the original point of the Tea Parties, so far as I can tell, was completely libertarian in nature and was to be as much a protest of the Republicans as it was of the Democrats.
Of course, if the Tea Parties had remained the sole province of a handful of libertarian activists, they never would have received the national attention they’re now able to receive, and thus would have had even less impact. By accepting the involvement of the movement conservative multitudes, the originators have lost control of their message even as the message has access to an ever-larger platform. The result? An incoherent jumble of protests that is going to wind up resembling the same sort of incoherence that has characterized large-scale protests and demonstrations for decades.