People bully you all the time because there's not much you can do about it and they know it.

The 'ol "I'm gonna get you fired, get me your manager, you're worthless, I'm a lawyer, I make more in a day than you do in a year," will be very familiar to anyone who's worked in retail, medicine, customer support, etc.

Just watched a lady pull that at the cable office the other day.

The employee just has to deal with it. Not much choice in the matter. Be polite, smile, apologize profusely, desperately wish they would just go away. The second you lose control of yourself, now it's your job on the line.

There will be times in your life where you don't hold all the cards, and the wrong person will take advantage of that. It's important to know exactly how those situations play out, and how to navigate them with a cool head under pressure. Especially when you're early in your career and mistakes can burn you down the road in terms of recommendations and stuff.

Dealing with a bully in 9th-grade gym class was where I learned to push-back without escalating. And after I learned to do that, well, I wasn't bullied anymore. It came in handy later-on down the road when I had to deal with similar situations in a customer-facing environment. I had a whole skillset associated with keeping a cool head under pressure, and that wound up being an extremely valuable skill to my employer.

It's something you can't learn from a book or a website, you just have to navigate these situations under pressure over, and over again until you figure out how best to handle them within the constraints of your own personality. Most kids do that at school in a low-stakes environment.