You know how there is the Golden Rule: "Treat others how you want to be treated." There's another really good rule I wish more people followed. If someone can't change something in five seconds, don't say anything. So if you are judging someone for their height, weight, or anything that is something that is a part of who they are, just keep your mouth shut.
That's what one teen wished a fellow customer at a bakery had done, but sometimes you have to stand up for yourself when others are trying to tear you down.