Someone at a restaurant in Delaware missed the class where they explain that the usual place to vent racially biased frustration at a customer is on the receipt, as the eatery is now having to do a lot of apologizing for things that showed up on its Instagram page.

According to the News Journal of Wilmington, an Instragram account that appeared to be associated with a pan-Asian restaurant recently posted three receipts from bad tippers.

That alone is nothing new — though it’s certainly gotten people fired before.

What made these receipts so problematic is that they, and some photos of patrons at the restaurant, were the insults directed at the customers.

Like the customer with what is described as an Indian surname. The diner left less than 10% tip, per the receipt posted online. Whoever posted it to Instagram commented, “What do you expect from a last name like that?”

Confusingly, this photo also had the hashtags “#cheap #jew.”

The Instagram uploader was more certain of another diner’s ethnic background, writing “#cheap #jerk #indian” for another customers with an Indian last name.

The account also had a photo of a customer at the restaurant’s bar with the caption, “Cheap ass, order takeout and eat it at the bar #monday #cheap #trash.”

The restaurant’s Facebook page also included a couple of angry status updates about bad tippers

There seems to be some confusion as to who maintained the Instagram account. The News Journal reports that the account belonged to the manager — a nephew of the owner — and that the profile photo on the account was a picture of him.

The manager, however, says that about a half-dozen other employees had access to the account and that it must have been one of them. He also claimed that one of his employees could have used his iPad or smartphone to post to those accounts without his knowledge.

“Maybe some staff just have grudges against customers who did stuff to them?” he theorized when confronted about the posts. “It’s not good to say that. If you’re on the clock, it’s not good to use [those names], it’s not professional. Outside of work, I can’t control what people do.”

The account has since been deleted.

“It’s so bad. I’m so embarrassed,” the owner said after finding out about the Instagram posts, adding that she knows nothing about any of the eatery’s social media pages.

She also defended the manager, saying “It was probably the waiters…. Now, if I figure out who will do this, I will fire them.”

Yesterday,NBC 10 in Philadelphia picked up the story. Since the original story was published, the owner placed her nephew/manager on unpaid leave. She also says she’s hired a social media consultant so that this sort of nonsense won’t happen again, and posted an apology letter on the restaurant’s door.

Want more consumer news? Visit our parent organization, Consumer Reports, for the latest on scams, recalls, and other consumer issues.