Executive pay, though treated in official government statistics as labor income, derives from control over business firms and really should be counted as property income.
Some examples of events that create the need for precautionary savings include health risk, business risk, unavoidable expenditures, and risk of labor income change, saving for retirement and child's education.
In case both rates were equal, given an anticipated shock to the labor income, rational individual would hold a large stock of assets to hedge for the income risk.