A couple of points though. First, there were a lot of "concrete assets" created in recent years. As simple evidence google "condo glut." Also, you're right - these business loans are fundamentally different. Unless I'm missing something, they're fundamentally riskier - there's no collateral (overvalued collateral is better than none), and the entity you loaned money to is FAR more likely to simply disappear.

As to whether they'll go to better uses - hey - I hope you're right. I hope it helps create more value / helps the economy, etc. However, plenty of people took money "out of equity" in loans and spent it on stuff that created value in a similar manner. For instance, there used to be quite a burgeoning business in selling solar panels to homeowners.. many would argue it's good for the environment, adds value to the home, etc. The interesting part here though is that the salesman weren't really just selling solar panels. Their job was to walk the homeowners through how to get the money in a mortgage "out of equity" on the always-rising value of their home and collect any tax credits available.