I really don't think there's an "established social norm" that you're expected to suffer a loss of hundreds of thousands of dollars when you don't legally have to. In a normal housing market, people pay their mortgages not because it's the moral thing to do, but because if they don't they'll lose the house and have their credit trashed. Only recently have banks made large numbers of loans where those deterrents are insufficient. It seems perfectly reasonable that since both the banks and the homebuyers made foolish decisions, they should share the pain.