This has become the famous quote for customers. Naturally it sounds good for all of us as we are all customers. Even though we who have the right to complain and comment, we should do it with respect of the person concerned. Everyone has feelings no doubt but we need to be conscious of who we are. Of course, we want to be treated nicely and it's the same for the other side.
If we need to complain, there's a proper way to do it. We shouldn't do it in front of so many other customers or in public. It is not respectful. Surely there's a proper channel to do so.
I hope all customers have the conscience to be good customers and support the person concerned.