Frontline (I think it was) many years ago ran an episode on 401k plans. There was a medium sized company that offered an identical 401k plan to all its employees, from the bottom to the top salary levels.

They found that the higher the income level, the better percentage returns the employee had on the plan. The lower, the worse performance.

The 401k plan offered several investment options.

Clearly, the higher income people were making better investment decisions. The conclusion was the company was going to offer seminars on basic investing, though who knows how that turned out.

There's a lot more to personal finance than balancing a checkbook, though many can't do that, either.