It sounds like debts are sold in such bulk that there's no way to do something very targeted, like starting an org in your town to buy debt from your ZIP and collecting contributions to cancel your neighbors' debts, but if these debts are already only worth 5¢ on the dollar to the sellers, it seems like it would make quite a news story if you could.
If I could buy up $2000 of my neighbors' debt for $100 and remove that burden from them? I think I would, at least occasionally.
But even if you don't assume goodwill, if the whole community knew the plan was to buy and cancel everyone's debt, you could probably get the debtors themselves to band together to do it!