But as more Dodd-Frank-related banking regulations come on line, bank analysts believe it will drive flow to the nonbank part of the lending framework.
Consumer loan demand is finally beginning to rise after a lackluster 2013, with the third quarter showing household debt rising 2.7 percent and business debt up 5.2 percent, according to the Federal Reserve.
"In advanced markets, various types of funds have been stepping in to provide long-term credit to the private sector as banks have been lending less," the FSB said. "In fact, lending by shadow banks contributes significantly to total lending in the United States and is rising in the euro area."
Indeed, banking analyst Dick Bove said the new regulatory framework is providing a direct feeding tube to shadow banks.
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In a note to clients, the vice president of equity research at Rafferty Capital Markets said he has "projected repeatedly that the actions of the government and the bank regulators would stimulate the creation of a huge, unregulated shadow banking system. Well this is no longer a projection; it is a reality."
The industry, which features multiple components such as basic storefront lenders as well as insurance companies, hedge funds and real estate investment trusts, is getting more company, from peer-to-peer lenders. LendingClub staged a highly successful initial public offering earlier in December, raising $870 million in its debut, and others are expected to follow in 2015.
"The regulators have set the stage for the growth of the shadow banking sector," Bove said. "They have created a system with more risk than the one that existed before. However, with risk comes opportunity. I expect that we shall see more opportunity in nonbank stocks than banks for some time."
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Those risks also were noted by the FSB, which said the U.S. has particularly high exposure among global economies.
"The GFSR finds that in the United States, shadow banking accounts for at least a third of total systemic risk, (measured as extreme, low-probability losses to the financial system), similar to that of banks," the board said. "This contribution to systemic risk has been growing since the global financial crisis."
At more than $24 trillion, the U.S. has the largest exposure of any reporting country, followed by the U.K. and China. Despite its own government restrictions, China's shadow system, at about $4.5 trillion, has been growing about 34 percent annually in recent years, according to S&P and Thomson Reuters.
Fed Vice Chair Stanley Fischer addressed shadow banking growth several times in 2014.
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"Among the most important of the possible unintended consequences is that toughened regulation of banks will move some financial activity out of the banking system and into the shadow banking system," he said in August.
Following up those concerns, he said at a symposium earlier this month that "we have not started to deal with the problem of shadow banks."