No, that's Hanlon's Razor. Either the population was ignorant of living beyond their means and adopting bad economic policies -- or they are deadbeats who willfully took out credit they had no intention of repaying.
The population is not the one who adopts the economic policies. The government is.
Governments are elected by the population. Are they then not responsible for their choices?
The elected party in Greece only got 40% of the votes and they can pass any law and take any decision at will. In addition to that pretty much every party that was elected in the past had been caught lying regarding most things that they said regarding the economy (and not only). People should certainly be responsible for their choices, but this was not one of them.