How much does customer loyalty cost?

A customer accidentally had a home repair issue and needed a replacement part.   When he called the manufacturer, he was informed that the item he needed was not sold separately from the entire unit.  

However, the customer service rep told him that he could send the replacement part, free of charge and with free shipping, just for being a loyal customer.  

This level of customer service, and subsequent customer satisfaction, comes from senior leadership empowering front line employees with the ability to make decisions like this. For the cost of one replacement part of a product, the company won a customer for life.  

How are you empowering your front line employees?