If you buy $10k of debt for $500, the debt buying business' basis in the debt is $500. If they cancel it, they can deduct $500.
If $10k of your debt is forgiven, you get 1099-C'ed for $10k in income.
Net-net, this would cause $9.5k in income if you went through with it.
Until everyone starts doing this and the whole system collapses, at least. That money isn't coming from thin air.