Um, what? How is the Troika buying debt? I seriously din't get what you are trying to say. Would you like to buy my debts? I guarantee you ridiculous profits.
Privatising services? You mean selling state companies/land/isles to private market entities?
You can't compare personal debts to gov't debts. People buy gov't debts all the time. It's called bonds. No one will buy your personal debts because, frankly, we know you will never pay it back. Gov't debts are sold to raise money for public projects like bridges, highways, ports, etc which in turn generates revenue to pay the bond-holders. I had invested a few hundred $$$'s in US Treasury bills and they have become pretty valuable. If I had bought your personal debts, I will have lost my shirts. Do you see the difference?
Everyone knows Greece, neither basically any country will ever pay their debts. The debt is still increasing at faster rates than what can be paid for.