There is no such thing as a "vulture fund", this is just pure propaganda. There is a bond market, people buy and sell bonds, if people weren't able to sell their bonds they wouldnt buy them in the first place. This is an explicit part of the arrangement. If a country doesnt want to be involved with "vulture funds" then they should have written into their loan agreements that they are non transferrable.Good luck with that idea ! Or perhaps the debtors may want to compensate the original buyers of the bonds who were forced to sell at a loss ?
As for "taking food" from the mouths of poor argentina babies, where does this come from ? The government can choose how it spents its money, it can choose to pay its debts, it can choose to feed babies or it can have football para todos and subsidise state funded TV propaganda.
Third world debt is a problem (although I dont consider Argentina to be a third world country), but it is for the international community, the world bank, the IMF and the regional goverments (EU etc) to resolve these issues. It is not the role of individual creditors to resolve the economic problems of errant borrowers.
People invest in the bond market and will use the law to recover debts. People borrow money and some of them use the law to avoid paying their debts ( or ignore it completely). Thats the way of the world, it makes good theatre for us bystanders.