The rhetoric against austerity seems to be that we don't want to hurt the people (especially the economically disadvantaged) but I don't see a bright future in the near-term whichever way the Greeks vote. (I know, this is such a terrible thing to say. Good thing I am not in politics.)
Yes high food prices are a problem but without tyrannical corruption like we see in Egypt this problem fixes itself over time.
"Austerity" seems like a red herring to me. The Germans were only too happy about Greek entitlements when they were driving Greek borrowing. Now that they're shutting off the tap (and why now rather than five years ago?), the Greeks themselves will figure out how to distribute the food. I'm sure they'll come up with something, and that plan will have come from Athens rather than Brussels or Frankfurt.
Also much of anger on the street has been due to lower living standards (euphemistically referred to "internal devaluation") So a true devaluation via an independent drachma won't go over well either.
Of course, the rich keep their money far away from Greece. It's the masses who will suffer.
Worse, any political instability will cause more problems for their critical tourism industry.