The real problem is that banks lent to Greece without doing their due diligence evaluating risk. Instead the bankers collected their fat fees for making the loans. Usually when banks make bad loans they have to write them off but when in 2010 the Troika (Euro Community, IMF, ECB) took over the Greek debt they paid 100% instead of insisting on the banks taking a "haircut" of say 50%. In truth some of the smaller membe…
The Troika indeed has made private creditors take much more than a "say 50%" haircut, in their second bailout package from the 21st of February 2012, the "Second Economic Adjustment Programme for Greece". The private creditors took a 53% cut in principal payments, a massive extension of the term and a reduction in interest rate - they lost maybe 70-75% of their money in present value terms.
And of course, if the Greeks would have been forced into default in 2010 as you demand, none of the subsequent €200bn+ Troika bailouts would have happened - the starvation would have set in 5 years earlier as the country would have had no chance to cover their primary deficits - even without debt repayments.