A while back, I'm the only person doing checkout and there's one other person working returns/ customer service. That person inexplicably up and leaves for lunch without getting a relief person for either of us.

I'm working the long checkout line and a return customer walks over and yells in my face, "Hey do you see us over here!" I politely but sternly say back "I'm not going to do two things at once. I'm going to service the checkout line. You'll have to wait until a person services the return line."

Finally, after 15-20 excruciating minutes, a relief person comes up to work the returns. After being helped, that woman who yelled at me walked out right past me with her middle school aged son, no apology, no nothing.

I did feel good for sticking up for myself that day because previous me might have tried to do something stupid like work both lines simultaneously.