I don't think it's fair that retail employees have to deal with so much from customers. They're expected to always be polite and nice to customers, and will get in trouble if they're not. But the customers can be rude and nasty to retail employees without consequences. Not only that, but customers behave like they can't read signs, they can't reach for anything by themselves, and they don't know how to look for things on their own - either they're lazy or just needy and wanting to treat retail employees like servants. At least, that's how most retail employees like me feel about customers.
It's hard, as a Christian, to have empathy and see customers as actual human people with lives and jobs of their own, instead of just 'customers'. But, if you think about it, Jesus' ministry was almost entirely about customer service. And, he treated everybody with respect and patience, regardless of their endless requests and questions. We are called to behave like Jesus in how he treats people. It's difficult, but I'm trying.