You have to be careful here because you're trying to make sure that people are happy, not fat and happy. Complacency eventually threatens the livelihood of your employees, and that is stressful at any company, but the magnitude of that change is greater when everyone has been bopping along without a care in the world.

Being happy is not a capitalistic goal and the capitalists will eat your lunch. Being happy and kicking ass is close enough to be harder to sabotage.