#BBCTrending: Check shaming churlish customers
When restaurant patrons pay with credit cards, their names are printed on their receipts.
And when those patrons behave badly - if they are sexist, rude, or leave a too-small gratuity - wait staff looking for retribution have been known to post those receipts online.
There's the African-American Red Lobster waitress who posted a receipt with a racial slur scrawled across it and the bartender who used a receipt to identify a man she says groped her.
One waitress posted to Reddit the receipt of a pastor who declined to leave a customary 18% tip because, "I only give God 10% - why should you get 18[?]"
It's called "cheque shaming" and it's become increasingly common in the age of smart phones and photo sharing.
The practice often results in big clicks - and big consequences.
Post like these tend to trend quickly because they play on some of the best and worst impulses of the online community. People want justice for the wronged servers, but aren't interested in finding out the whole story.
"We definitely have a mob mentality, and that mob mentality online screams 'shoot first, ask questions later'," says Peter Shankman, a customer service consultant who specialises in social media.
But the "impulse decision" to post a receipt has long-lasting consequences, he says.
"It is probably a given that not only are you going to get fired but it's probably going to be pretty hard to get hired again," he says.
"It's very easy to Google your name. It's very easy to see what you posted. And these are the kind of things that, while it might feel great to get five million views shaming someone who didn't leave you a tip, on the flipside, that is going to come back to you."
Red Lobster is being sued by the man identified online as having written the slur - he denies it was him. The bartender has had to face angry accusations from the man she named. And the waitress who posted the pastor's receipt was fired.
The BBC spoke to the owner of a Philadelphia restaurant about why he decided to cheque-shame a customer and what happened once he did.
Filmed and edited by Ilya Shnitser
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