If they anticipated a bust they would have prepared for it, taken measures to prevent it, and thus stopped it from happening. A crunch means that very few people were defensive with their money. For example, if people kept a percentage of their assets in gold and cash equivalents, the stock market would be less prone to extremes. As it did in 1929 when it started a depression, another great stock crash can lead to the same kind of plunge in business activity. Confidence fades fast in a financial crisis.
Consumer spending slows way down and savings rise.
With the amount of credit card debt, consumer loans and extremes of leverage throughout the financial system a stiff recession can turn nasty. That's when people lose their jobs, can't pay their bills, have their cars repossessed and lose their homes. That's when the credit card companies look to the government to bail them out. They may have to get in line. People believe corporate and government bonds, treasury bills and money market funds are absolutely safe and look at them as a hedge against an economic crash.