I think Golden Dawn's existence grew not because of people's struggles with the current economical and societal situation, but on the machiavellian interests of some parties in the Greek parliament that coincidentally could have been involved in creating the dramatic situation of the current economical crisis.

In late 2011 when the main "hit" of political struggle had struck Greece (for months some streets of Athens, and to an extent some in Thessaloniki were housing some of the biggest marches of this government) Golden Dawn was one of the inhibitors of violence and extremist ideas, along with some anarchistic parties and to an extent the communists.

Coincidentally at the time not much was said about Golden Dawn, until in 2012 it got too big. They had weapons, they had numbers and were steadily growing. That's when the so-called democratic leaders of Greece chose to move against Golden Dawn, and they used a single murder to turn the tables around.

Until that point Golden Dawn wasn't disturbed. The police force on the higher levels closed an eye to their activities, and somewhat to the violence, people were speculating a lot that the majority of the police was filled with Golden Dawn supporters because of that. (And due to the fact that at the time, police salaries were steadily decreasing, Golden Dawn being one of the parties that due to its authoritarian nature supported the military and police increase of salary and benefits)

So, what took place in late 2011 during this interesting time was that the whole high level military staff was sent off for retirement and replaced quickly throughout a single week. This incident was both underreported, and purposely hidden by the media. The news only circulated on some independent sites on the net, and only brief mentions of it on some news.

There's little proof to correlate the incident that Golden Dawn benefitted because of Samaras' government, but the times, growth, and the response of the political powers in Greece since 2012 to the controversial party all match with the growth, and fall of the Samaras government that just further dug up a grave for the country.

My theory is that well, Golden Dawn was just a pawn all along. A bunch of wild dogs to bark and maybe bruise some people here and there to make drama. Until the situation with the EU got too stressful and the Greek government couldn't exactly just make demands; by that point the EU's and ECB's "suggestions" were exactly like orders. Since that got out of hand, some people in Athens whose lives were -struck- by the crisis found an answer in the right-wing nature of Golden Dawn and supported it, and it helped in its increase in popularity, its pool of human talent, its political presence and all sorts of things that can help to a prelude of a military or fascist coup d'etat.

Similarly, people who were angry with the EU policies and treatment of the country, but not enough invested in being far right, turned their gaze to Syriza. However, in the EU, and inside the country nobody wants a political power that has the guts or at least, their hands stained with all sorts of shady things that took place in this small country. (If anything, Tsipras' party is the cleanest one in the country right now-- just to give you an idea on how deep the rabbit hole goes)

I wouldn't be surprised if in 50 or 60 years someone involved in these incidents comes off clean with some kind of book or document that explains some of the shit that went down during late 2011 and 2012.