Unfortunately, people in customer service jobs in general get some of the worst treatment by others, and it doesn't help if you are younger and you get an adult who feels they don't have to treat you as another human being because you are younger. There ARE kids with a lack of responsibility and ethics, I think some of that is upbringing, but they often go on to be ADULTS without a good work ethic too.
Customer service jobs in general though, even adults working in them, take a lot of verbal abuse. It is really why I couldn't wait to get out of customer service when I was younger. Unfortunately that is mostly what is available for kids needing a summer or part time job, so often their first work experiences are very stressful and unpleasant. It takes time to learn how to do things that other people have been doing for years, such as instantly know how much change is due back from a large bill. And then people often automatically assume the worst if a mistake is made, that the employee is doing it on purpose.
Unpleasant as it is, you can take the experience and always remember as you go through life and deal with other customer service people. You can smile and treat them as a person, and be patient with errors and not assume the worst, when you know what it's like on the other end. You can really make a difference in a harried person's day when you treat them with compassion and understanding instead of blowing up when a delay or mistake happens. You can turn the bad into something good later on. Just continue to take the higher road than people who have to behave with such rudeness and hurtfulness.
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