If you buy a bond and it turns out to be worth less than you paid for it, then you get equity after bankruptcy resolution.

If you buy public debt of a sub-sovereign entity you're counting on the sovereign to make you whole. Too bad the Eurozone has no sovereign but the ECB and the ECB making German creditors whole gives Germans stomach ache.

If you are not convinced, try it on someone who has not been entirely debauched by economics. — Piero Sraffa