That's the general portrayal abroad. If you want my personal experience for clarification i can say that it's certainly widespread, but mostly in the higher echelons.
It doesn't matter if it's the private or public sector, usually the most effectively and heavily taxed are the lower echelons of both: the more you earn, the easier it seems to avoid taxes. This has a lot to do with the fact that money and connections are things that influence each other and end up in a self-feeding cycle, with certain people growing too big for their shoes at the expense of the mass that does its job, servers in the army (we still have conscription) and pays taxes.
In other words, those who got us into this mess by evading taxes, making bad investments and dodging any kind of contribution to the "team effort" so to speak, are the ones who now expect us to foot the bill
The previous PM for example, the first time he was about to resign due to public pressure (100-150 thousand people demonstrating outside the house of parliament last July/Auhust), he was prevented by his family members. His brother is a CDS holders who stands to directly gain from the country defaulting.
I too don't want to go into specific politics because it's my job to enforce the rules here and there's a no politics rule, so i'll just end it here. I think it's just sad that we've been pitted against each other as people of Europe (perfect smokescreen for those that want to finish up the job of taking away our citizen rights), while the actual dealings are quite easy to perceive. It's a complex situation and in the case of Greece it's also a geopolitical issue, with many major powers competing for access and influence to the region, often in a manner that directly violates our interests (within our own borders, not across the globe) and dominion rights.
I don't want to say more because this is exactly the kind of topic that tends to inflame discussions.