When you've worked in customer service, you relate to those still working customer service. The tolerance level and understanding will always stick with you for years to come because of the horrendous things you've seen during your time working in the field.
Anything that requires you to interact with the customer is considered customer service. And people who say " well that's what you're paid to do," are wrong. I'm not paid so you can take an emotionally-charged power dump on me. I'm paid to help you through your question, cash you out, or fulfill the service I was hired to do. Whatever happened in your day is your business and needs to be worked out by YOU.
Throwing emotionally-stunted reviews only discredits your position, not raise it.