It's a shame to destroy such a popular conservative narrative, but once again, those pesky "fact-things" keep getting in the way!
Greece’s government expenditures were basically stable through the ’90s and most of the 2000s, increasing rapidly only as a result of the 2008 recession (until the austerity programs began to take effect in 2010). Moreover, Greece was not a massive outlier in terms of government spending levels. Prior to the crisis, Greek public spending as a percentage of GDP was on the lower end compared to France, Italy, and Germany:
But as with most of the other troubled eurozone economies, the major problem for Greece, the authors conclude, can be found in the private sector financial balances:
[G]rowth in Greece during the 2000s—similar to the United States—was fueled by consumption financed by running down households’ financial assets, and/or by net borrowing. It was this unsustainable process, rather than an excessive government deficit, that put Greece on an unsustainable path.