I'm 19, and I'm a cashier in Canada. The city I live in is mostly filled with really nice people. This was my first job, and I had my first ever rude customer, who caught me off guard. My story isn't as wowing as the stories here, but anyway.
Old lady: (silence)
Some people don't say hi back, which I don't mind at all.
Me: How are you?
I say that in case maybe she didn't hear me, and I'm just being polite.
At this point, I know she isn't much of a talker. I'm completely fine with this, many people are like this.
Me: So your total comes to [..]. Go ahead.
She then put in her card the wrong way, and had to readjust her card. No problems so far.
The receipt is printed. And as I'm about to hand it to her she says.
OL: something something (couldn't hear her) thank you? (She had this death stare)
OL: Won't you say thank you?
Usually, as soon as I give the customer their receipt, I say have a good day or good night. So I was REALLY confused.
Me: (Super confused look) Uhh... Okay... Thank youuuu (sarcasm) have a good day! (obvious sarcasm)
The two other customers in line behind her laughed at the whole thing after she left.
I don't think she was extremely rude compared to what I've seen here. But it was the first experience that truly caught me off guard lol.