Try working at a fast food place. I was a grill and sometimes sandwich prepper at Wendys for a little during my high school days. One time I prepped a sandwich and accidentally put pickles on the burger. Customer came back and demanded a new sandwich. Not sure if there is a pickle allergy out there but they could have just taken the damn pickles off.
Customers are annoying. Scratch that... People are annoying. That is why I try never to hold any type of job that has to deal with customers. I did do a customer service rep for a company that was contracted by Comcast for 6 months after college. Those were interesting days... That was when Comcast was trying to get rid of the old land lines and go to VoIP. Let me just say there were tons of pissed off customers.
