... Some Wall Street analysts assert that CEO Jim Sinegal is overly generous not only to Costco's customers but to its workers as well. Costco's average pay, for example, is $17 an hour, 42 percent higher than its fiercest rival, Sam's Club. And Costco's health plan makes those at many other retailers look Scroogish. One analyst, Bill Dreher of Deutsche Bank, complained last year that at Costco "it's better to be an employee or a customer than a shareholder." Mr. Sinegal begs to differ. ...Good wages and benefits are why Costco has extremely low rates of turnover and theft by...