re: High fees for Mutual funds

Why don't people just use common sense. Assume a 7% real return on public equity, it might only be 4% in the future. Net of inflation you might earn 7% before any other fees, why does anyone willingly choose to go with an advisor who likely adds another 2% in fees, then trading commissions and b/a spreads by high turnover funds of another 1.5%. Where is the return for the retail investor if the real return is only 4% prior to all of the other costs? My advice is to avoid high investment costs, which would mean DIY investing in vehicles that gives one exposure to multiple asset classes efficiently at low cost, just like gazillions of informed DIY'ers do. I don't understand why the article would surprise anyone whose head is not buried in the sand.