I tried to find the source of the Zero Hedge story and if you google "Greek parliament tunnel" all you get is blogs and forums of varying degrees of nuttiness.

Zero Hedge sources it from Covering Delta,

is the blog for [the] radio show "Covering the Spread," that airs on Tuesday nights, between 7pm-8pm on 91.5FM WNYE New York. [They] cover the latest in Finance, Politics and the in-between.

The blogger is a libertarian/Austrian. Sunday, they posted The Mood in Constitution Square and the Lead-up to June 15th

The people currently gathered in Constitution Square have no more in common with each other than any other two random Greeks that you would find on the street. Some are unemployed. Some are pensioners. Some are students. Some are angry, others are despondent, and many are just there to pick up chicks.

Still, they do all seem to share one belief, and this is that the latest memorandum is bad for the country. Some falsely believe that putting an end to the memorandum and to the new IMF intervention will mean an end to austerity. Others believe that a return to the Drachma is a solution. Still others believe that solution can be found in the tenants of communism - yes, unfortunately communism is still alive and well in Athens.

However, the majority of those who I have spoken to agree that Greeks are to blame for their problems, and that a dismantling of the "rousfeti" economy seeped in bureaucracy and socialist dogma is necessary in order to improve the competitiveness of the country. This is encouraging, and equally encouraging is the recognition by this same majority that just because we are responsible for the situation that we now find ourselves in does not mean that we have the obligation, the responsibility and even the right to sell our country to a group of predator banks and multination corporations that worked alongside a generation of corrupt politicians to create a debt so large that it could never be repaid. Many Greeks are not responsible for even a penny of this debt, but even if they were, no Greek alive today has a right to sell that which is not his. Who told these parliamentarians and foreign dignitaries that they have the right to sign away this land to private corporations? What would our forefathers, who fought and bled for our right to even have a country of our own and a functioning parliament, say in response to this treason?

Economics is politics by other means