ELIZABETH HARRIS writes about how foolish people can be:

New research from the field of behavioral finance, which draws on psychology and economics, provides data on the disconnect between the desire to prepare for retirement and the failure to do so. Researchers have found that for many investors, the task of sifting through pamphlets about their company's 401(k) plans ranges from unpleasant to horrible.
Some people end up doing nothing when confronted with the need to pick savings goals, select appropriate asset allocations, screen investment choices and rebalance their portfolios regularly.

So the oppressive corporations step in to do it for them.