Confusion about when we are the customer

In our modern, entitled, self-serving consumer culture, we tend to be confused about when we are the customer or not. If we work for pay, our job is to do something to benefit someone else -- our customer. We are not the customer in this scenario, someone else is. We are supposed to make someone else's life easier or better. In our job role, are we serving our customer, or do we expect to be served? This mindset probably does more than anything to determine if we are useful.