Any Greek with any sense would want to take his money out of the banks. He would then be holding cash euros, which will be worth at least double the drachma amount in bank accounts when Greece leaves the Eurozone. The same thing happened in Argentina when it defaulted. Its currency had been pegged to the US dollar, but when the banks closed no-one could get hold of their money, and when they reopened the value of their deposits had halved in real terms, as the Argentine peso crashed against the dollar. In Argentina it made sense to hold cash dollars, in Greece it would be folding euros (or gold and silver of course).
It is a truism that Greece should never have been in the Eurozone, the way it fudged its figures to get in has become the stuff of legend. The Eurocrats should not have allowed it, but it seems belief in the Projekt outweighs reality every time. But remind me, in ancient Greek mythology, what was that thing which follows hubris?
I never tire of saying this ... all Eurozone members fudged their figures to get into the Euro (except Luxembourg). In other words, only Luxembourg actually fulfilled all of the "Maastricht criteria" for entry.
Greece's fudge back in 1999 wasn't that bad comparatively.
It's only after 2004 that Greece's public finances fell apart completely because the 2004-2009 government neglected to collect taxes due ... for electoral purposes.