It's not so much that the banks are pushing this solution themselves, but that they are preventing exchanges from having ready access to cash and being able to convert to fiat. Kraken has complained of this in the U.S., where banks are locked up tight and it's had trouble finding a U.S. partner. Over the last week or two, the Bank of China's pressure on exchanges has been the subject of a number of news articles. To be fair to the U.S. banks, they are worried about complying with anti-money laundering laws. But if BitUSD or some solid alternative were available, then it would prevent the need to rely as much on banks. And per that article I linked to in my original post, it looks like even some Chinese exchanges are considering that a layer of fake money or P2P exchanging could make good sense. So the market is coming around to this, even if the push is unintentional.