Likewise, savers who had put their 401(k)s into gold would have done well the past two years, and might continue to in the future against the backdrop of a falling stock market. A 401(k) heavily weighted in U.S. treasuries would also come out ahead, said Weller, if treasuries were held long-term.
Sorrell's worries are mitigated by his youth.
"I'm 39," he said. "If my 401(k) plummets, of course I'd be concerned. But longer term, I think the stock market will have recovered by the time I need to tap my savings for retirement."
A crash actually could represent a buying opportunity, he said, with temporarily depressed stocks available on the cheap.
"If you'd bought Bank of America nine months ago," he noted, "You'd have made a tidy profit."
Sorrell's greater worry is how a default might affect the tourist business and how a worsening U.S. economy might discourage foreigners from coming to New York.
"Look at Greece," he said. "The travel business there is just bleeding away. If we, here, defaulted, then some tours from abroad would be canceled. My business could be very badly hurt. Professionally, that's my real worry."
ABC News' Dan Arnall contributed to this report.