Defaulting on a debt is not about shame. Governments don't feel shame. The ramifications are that future credit becomes much more expensive, as the next contract's debt provisions will be harsher.

> No surprise that it's mainly bankers pushing the "it's immoral to default" line.

Plenty of honest, hard-working individuals pride themselves on always paying their debts. Similarly there are those who think that you shouldn't extend yourself beyond your means. It's not just bankers who consider not paying dues to be immoral.