On my way back from the Midwest two weeks I flew on Midwest Airlines. In their in flight magazine MyMidwest.

One of their articles was a feature of Chip Conley and the founder boutique hotel operator in California, Joie de Vivre.

“There have been many studies that show that if you treat employees really well, it pays off enormously in productivity, profitability and customer retention,” Conley says. So why doesn’t every company implement such smart management? “They get stunted by short-term thinking and focusing too much on the easily measured basic needs,” Conley explains. “To do it right is much, much harder.”
[...]
“Other hotels sell sleep; we sell dreams,” Conley says. The intended result is that after a guest stays at a JdV hotel, he or she feels an “identity refreshment.” Guests are so pleased that they tell their friends, making word-of-mouth the company’s strongest advertising technique.
– The Boutique Mystique MyMidwest Sep/Oct 2008

When people refer to studies I want to know what they are. If the studies can show the pay off, it must be measurable — even if it is more difficult.