The percentage of middle-class families who keep their money under the mattres is very small. Most middle-class folks have their money at Wall Street and I am sure many of them changed their mind when they lost 10% of their wealth in just 3 hours.
Letting the markets work this out by themselves through bancruptcies is a bad idea in general. If the roof of your house is leaking – you don’t tear down your house and rebuid it to solve the leaking roof problem. The 700b plan was putting a bucket under the drip. Temporary short term solution, but a mandatory step before fixing the roof.