This works for airlines because compliments for employees are unsolicited and customers mostly have to go out of their way to give them. As a result, if one is

This works for airlines because compliments for employees are unsolicited and customers mostly have to go out of their way to give them. As a result, if one is given you can be pretty sure it's both genuine and meaningful. As soon as you apply a metric to feedback, though, the effectiveness goes out the window. For example, I spent some time in the automotive customer experience world and car dealers routinely abuse the hell out of feedback systems by pressuring customers into providing positive scores and comments. Similar things happen when you try to use feedback systems like this as a component of internal review processes - they tend to get gamed extremely quickly.