When interviewed by GAO researchers, many small-business owners said they would  like to offer some kind of retirement support for their workers. But there were just too many obstacles that a business with limited infrastructure could overcome.

"When we met with small employers and other stakeholders, they identified a variety of factors as challenges to sponsoring retirement plans or as reasons for terminating existing plans," the GAO report said.

"One commonly cited concern focused on the multiplicity of plan types and the burden of paperwork and administration. For example, some small employers and retirement experts said that the broad range of plan types and features made it difficult for small employers to compare and choose plans. Another small employer who previously sponsored a 401(k) plan with a company match cited the amount of required plan paperwork. … In addition to these challenges, smaller or newer firms may be unwilling or unable to sponsor plans because they lack sufficient financial resources, time, and personnel."

The GAO explored the possibility that multi-employer retirement plans might take up some of the slack in plan offerings. But here, the GAO found there has been little action to date.

"Overall, no consensus existed among MEP representatives and pension experts on the potential for MEPs to substantially expand coverage. Large associations can provide the option of joining a MEP to their members. That option is unavailable to small employers not part of a membership organization looking out for their interests," the researchers said.

"The potential advantages of multiple employer plan design are appealing in this context. (But) current data and information, as well as other safeguards, will be necessary to ensure that small employer interests are protected and promises to participants are not broken," the report said.

The GAO also noted there may exist "low employee demand for an employer-sponsored plan."

It said employers found that workers would rather have health benefits than retirement benefits when asked to chose between the two.  While that may not really be the same as not wanting retirement bennies, it does illustrate the dire situation for small business workers that the GAO identified.

"For workers at small employers, building an adequate level of income for retirement is becoming increasingly challenging," the report concluded. "Particularly for small employers, the low level of plan sponsorship means that many of their workers may enter retirement with little or no income outside of Social Security."