http://www.washingtonpost.com/blogs/wonkblog/wp/2015/07/05/7...
http://www.washingtonpost.com/blogs/wonkblog/wp/2015/07/05/7...
However that's a generational change: Greece can't and won't be fast enough to do this and will never be able to meet it's creditors. Greece shouldn't have been admitted into the Euro in the early 2000s, this is now the result of that unwise decision.
"A 32-year-old chef in Athens says his income taxes are automatically deducted from his monthly paychecks. But every time he buys something and is given an option to pay less if he doesn’t ask for a receipt, he says yes."
[1] http://www.wsj.com/articles/greece-struggles-to-get-citizens...
As of 2010, Greece collected annual taxes equal to about "34% of the country's total gross domestic product (GDP) - slightly below the EU average of 38.5%." from: http://www.bbc.com/news/magazine-33479946
I do not think that they are correct.