It escapes my imagination to understand why Greece cannot call its wealthy class to live up to its responsibility. Let me not be petty about it. Let’s just assume that we are talking only about people who have, in Greece, material assets in excess of 1 MEUR. Most of those people do not live from hand to mouth. More importantly, perhaps many of those people acquired their assets bypassing the tax system.
Let’s not look for scapegoats. Instead, let’s just think about responsibility.
It becomes increasingly difficult to explain to voters in the North why they have a responsibility, why it is in their interest, to support Greece financially. It should be extremely easy to convince Greece’s wealthy class that they have a responsibility. It should also be in their interest because all of them should worry that, potentially, the economic crisis could lead to political instability (with all sorts of unimaginable consequences for the wealthy class).
I can only speak for Austria and Germany. In these two countries, it is EXTREMELY difficult to make larger asset purchases with unofficial (black) money. One instrument applied is, for example, a cross-check between purchases of real estate and personal tax declarations. As a rule of thumb, someone who has a lot of black money has to resign himself to the fact that he can only spend it safely outside his home country in larger amounts.
There are various ways to call a wealthy class to responsibility (solidarity tax, forced loans to the government, luxury taxes, etc.). The point is that it shouldn’t be a witch hunt. Instead, it should be a call to responsibility.
What would it mean to the wealthy class? The wealthy class would simply give back to society a little bit of the huge wealth which their society allowed them to accumulate! In a way, it would be a form of deferred patriotism.