Why are banks opposed to bankruptcy judge loan modifications?

I don't understand why banks would be opposed to having bankrutcy judges modify loan terms. I think of it this way; if there are 8 million families facing foreclosure and loans are modified to market value so people stay in their homes, wouldn't that significantly help our economy? It has been my observation that foreclosed homes sell below market value in order to get them to move plus there are additional costs besides loss of market value to the lender: loan servicer costs for attorney's, real estate commissions on sale of the home, inspector and maintenance fees, publication fees, etc.) I would say a very conservative estimate of these costs would be $20k per house. If you multiply that number by 8 million families, you get $160 trillion in additional costs to loss of market value that could be saved. I am agreeing more and more with what is unfortunately the minority in our government, that we should save these 8 million families instead of the greedy oligarchy. I am writing to my representatives and blogging in hope of making more people aware of this. Kudos to Senator Durbin for taking a stand.