Huffington Post Business offers an interesting article on employee happiness. According to a survey by the website Glassdoor, employees at Costco are happier than higher paid professionals at big name firms. What’s the secret to Costco’s success in making its employees smile? Employees appreciate the company’s healthcare plan. Costco’s CEO is an advocate for raising the minimum wage, and his company pays a minimum of $11.50 an hour. It pays to treat employees well. That’s Costco’s secret. Many employers could learn from its example.