Perhaps more troubling is that the study, based on a phone survey of 1,009 U.S. adults with $10,000 or more in investable assets, also found that plenty of participants aren't as aware as they should be of the penalties and potential long-term financial damage that can result.

Fifty-five percent of those with a 401(k) said that they understand the tax consequences of making an early withdrawal "extremely well," but 40 percent said that they understand the consequences just "somewhat well," and 5 percent said that they understand the consequences "not very well" or "not at all."

The study did find that the 401(k) continues to be a hugely popular retirement savings option, with nearly 90 percent of non-retired investors saying that they were taking advantage of a plan if it was offered at their place of employment. Ninety-six percent said they are actively contributing to their 401(k) and 93 percent said that they had reviewed the performance of their plan in the past year.

Early withdrawals are a problem, no doubt, but perhaps also an opportunity for plan advisors to offer sound advice. As the study said, "at a time when the U.S. savings rate is on the lower side of the historical range, investors with the capacity to save may need more guidance about how to save to avoid costly emergency measures, or having to take out loans or engage in early withdrawals."

Also read: Frittering away their 401(k)